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Handling A High Performance Jet
Tutorial By Dudley Henriques
International Fighter Pilots Fellowship
As you know, from time to time, I will take a subject that comprises some
degree of bulk of my weekly email from sim enthusiasts and write a general
tutorial on that subject.
Much of the email I get is from sim pilots flying light airplanes asking me
for tips on how to fly the high performance military jets.
MS, in their infinite wisdom, has created a program for us that anyone can
enjoy according to individual tastes. You can fly a J3 Cub and relax and
watch the scenery. You can load up a DC10 or a 747 and fly the ocean with a
load of passengers. And, for the adventurous among us, you can also attempt
to fly the world’s most high performance aircraft. Since my background in
aviation is associated with flying and testing high performance airplanes
both prop and jet, I have spent a lot of time with developers helping to
create accurate flight modeling and enjoying as well having these airplanes
on the simulator. By providing this tutorial for you, it is my hope that you
might enjoy the world of high performance jets a little more.
For those of you who have learned to fly with MSFS using a light General
Aviation airplane like a 172, there might be some transitional problems when
you first attempt to fly a very high performance jet. There are very
distinct differences in the way these airplanes have to be handled in real
life, and this flows over into MSFS as well, if the flight modeling is
accurate, and I’m here to tell you that for the jets I have on the
simulator, the flight modeling is extremely accurately duplicated.
Many of the world’s finest aircraft are now becoming available for insertion
into MSFS, and the market for these aircraft among flight simulator
enthusiasts is growing by leaps and bounds. The realism available to
developers at this point in time for recreating accurate flight modeling for
these aircraft is astounding, and I’ve discovered through testing some of
these products for developers, that what they are creating in graphic detail
and flight modeling in their presentation to the end user that presents the
performance of the actual aircraft is almost beyond belief to me as a pilot
who has flown some of these airplanes during my career.
Considering this, it has occurred to me that those of you purchasing these
marvelous jets might appreciate a few “tips from the perch” so to speak. I’d
like to give you a “head’s up” if I can, on some of the things you will find
different in the way these aircraft should be flown in the simulator, as
opposed to the light aircraft you might have learned to fly in the
simulator, so that you might enjoy the experience a bit more, (and hopefully
crash a bit less enjoying that experience J
Much of my real world experience in high performance jets involved
flight-test in the Northrop T38 Talon, which is incidentally the perfect
aircraft to use as a real world example for you on how to fly a high
performance jet.
Although there are many…many, fine examples of high performance jets
available for your use in MSFS, I have chosen to profile one that I happen
to believe are among the best available to use as examples in this tutorial;
the Captain Sim F104. (And NO, I don’t work for Captain Sim J)
I’ll give you some general information from my real world experience in the
T38, and project that into the F104 in the sim. This will give you a fairly
good look at the handling required for high performance airplanes in a delta
and modified delta low aspect ratio configuration that have high mass
fuselage loading, which is critical for you to understand if you are to
enjoy flying these aircraft in the simulator.
The reason the T38 is perfect as a real world example is that this airplane
was designed specifically to display the same handling qualities found in
much higher performance airplanes…. and trust me, the T38 Talon is a VERY
high performance airplane..
The word with the Talon among those of us who flew this wonderful aircraft
was that if you could fly the T38 well, you wouldn’t have any problems
transitioning into the more powerful jets. I can tell you this is true. The
T38 has the same fuselage loaded mass ratio (much longer fuselage to wing
ratio) that is found in airplanes like the F104, where fuselage length as
opposed to wing area dictate extremely careful and delicate handling in
flight, especially in the left corner of the envelope at or near the
aerodynamic limit line where departure and high sink rate are the result of
inattention to wing management, and the power curve can go back side in the
blink of an eye..
Ok…what do you have to know to fly one of these beasts without bending it…or
in your case…getting that God awful “you crashed” screen after sitting there
thinking you were right on the money using the old Cessna 172 techniques!!!?
First of all, right out of the box, you have to relearn some of what you
might have been doing with some of the other airplanes in the sim; not that
what you have been doing is necessarily wrong mind you, but what you have to
learn to do NOW to fly THIS airplane, might need a bit of “adjusting in
procedure”
Let’s take one of the highest performance jet fighters ever developed for
MSFS and learn a thing or two about how to handle it without bending any
sheet aluminum. The Captain Sim F104 Starfighter is handled much like the
T38 believe it or not. It’s just faster and heavier. The aerodynamics
involved and handling technique for the 38 is quite similar to the 104.
I believe by using the 104 for the sim example and the T38 for a real life
comparison, I can get many of you to where you can handle a hot fighter
fairly well.
First of all, let’s talk about throttle use for a moment.
In a light piston powered airplane, when you feed in power, you get fairly
fast response. The airplane reacts to your throttle input almost
immediately. Not so in a high performance jet.
The first thing you learn when checking out in airplanes like these is that
what the engine and the airplane do will occur AFTER you use the throttle.
What this means literally is that when flying these airplanes, you have to
be able to PROJECT mentally well ahead of what you want the airplane to do.
In aircraft like the T38 and the F104, you are ALWAYS well ahead of the
airplane throttle wise. The aircraft will do what you have projected it must
do, seconds AFTER you have applied the power to make that happen!
This becomes a real consideration on take offs and landings in these
airplanes, because it’s here you are the most vulnerable to mistakes, and
you don’t make mistakes in these airplanes in real life without severe
penalty, and if the programming for your sim aircraft is even close to being
accurate, you won’t get a second chance on your screen either!! J
The theory is of course simple, and most of you already know about thrust
lag in turbojet engines. The trick is in learning to apply what you know in
theory to practice, and this is the key here…PRACTICE! Practice allows you
to become PREPARED, and PREPARED is the key word to learn in flying a high
performance jet.
Proper throttle use in high performance jets begins the instant you touch
the power to move the airplane on the ground after starting the engine. Rule
one. NEVER pivot an airplane on the inside strut when you turn while
taxiing. Apply enough power to establish forward motion, THEN TURN! Rule
two. Apply just enough power to begin motion, and then back off the
throttle. Use as little power as is necessary to actually taxi the aircraft
and not a one % more. Brace your hand on the throttle base and use that as a
fulcrum to allow you to use your wrist in making extremely small power
adjustments while taxiing. This practice will come in handy later on when
you are on final and need very small increments of power for very small
changes in the approach profile.
OK…so we know that the airplane will always be behind the power, and we will
always have to be in front of the power!!
Takeoffs!
At first, doing a takeoff in a high performance jet seems simple enough. You
cram in the power, rotate at the right speed, and off you go. But wait a
second. To do it RIGHT, is to understand completely the differences between
a high performance jet takeoff and a light plane take off. Not only will
things be happening at a faster rate, but also now you have CRITICAL NUMBERS
to consider.
Remember this next sentence and don’t forget it. In the high performance
jet; on take off, you will be accelerating right through the rotation and
beyond. This means that you will have to BEAT the maximum numbers for
several high-end parameters that will be occurring extremely fast.
Hesitation, or missing those high-end parameters could mean overstressing
the airplane’s parts!!!
Just to give you some idea of what’s involved here, in real life, on the
take off run, you will have a max tire speed; max nose wheel on the runway
speed, a rotation speed for the gross weight, and a gear up/flaps up max
parameter speed that will be occurring extremely close to your rotation
speed!!!!! Take off in a high performance jet is no place to be caught
sleeping! You have to be sharp. You have to be quick, and you have to be
right.
First of all, in the simulator, some programs might allow you to compute a
take off distance required and some might not. Study your airplane’s takeoff
weight vs. runway length carefully if the information is available. Make
sure you have enough runway going out, and coming back in. If this
information isn’t available, I’d suggest a minimum of 8000 feet of runway to
play with these airplanes. That’s the figure for the Talon, and the 104
lands even faster than this. Considering gross weight and/or fuel on board,
the 104 can have a landing speed of 200 kts! Think about that for a second.
A 172’s Vmax is slower than this…174mph. Your F104 at 16K lbs will LAND at
this speed. Heavier, and it lands much faster then the 172 can FLY!
Obviously, the F104 is going to require your “undivided attention” J
Back to take offs;
In a light airplane, you accelerate to a rotation speed and take off. That
speed is very close to the Vy or Vx for that light airplane, and you
establish the right nose attitude immediately and configure for a normal
climb. In other words, in these lighter airplanes, you are basically stable
in climb fairly quickly after rotation. Not so in the high performance jet.
These airplanes rotate while in severe acceleration, and that acceleration
CONTINUES through rotation and into the climb. In real life we have a max
tire speed. Let me give you an example of how critical the rotation can be
in the T38 Talon, and you can compare this to your general aviation light
airplane.
On takeoff, you release brakes, go to max throttle (full AB) and immediately
watch for the burner light within 5 seconds. If no light, you abort
immediately. Assuming you get the AB light off, you’re immediately checking
the nozzles for opening, and the fuel flow. If everything is normal there,
you’re off to the races.
Now here is where the real difference begins. At 130kts, you initiate
backpressure and lift the nose wheel at 140kts. At 155kts you rotate the
airplane. While you’re doing all this, keep in mind the max tire speed for
the nose wheel on the runway is 174kts. J
Now keep in mind the aircraft is accelerating all through this rotation and
that THIS is what’s really different from flying a light airplane. It
basically means that instead of having all day to raise the gear, you have
SECONDS before you reach the max gear speed of 240kts and tear the gear and
doors off the airplane. Also, if you’ve used 60% flaps for takeoff, they
also have to be retracted before 240 kts. In other words, in a high
performance jet like the T38 or the F104, you are pretty busy cleaning up
the airplane at rotation, then pretty busy again establishing the correct
climb attitude, which in a T38, gives you 300kts initially.
The CS F104 on takeoff in the sim requires some pretty fast technique at
rotation to get it right. It’s important in the sim as it is in real life to
check your take off gross weights and configurations for the proper rotation
speeds and runway length. Just be thankful you don’t have to check the
density and temperature as well J
For a clean F104 at 20K lbs, you accelerate the airplane to 190 kts for
rotation. You make the run as you do in all high performance jets. You raise
the nose wheel about 5 degrees and no more until you rotate. In a real
airplane, getting the nose too high on take off can take you deep into drag
rise…in fact, so deep in some airplanes that the takeoff can’t be
accomplished. So you want just a bit of bite on that low aspect wing out
there. But not too much.
The rotation problem in these airplanes can be demonstrated with the CS 104.
At 190kts, you EASE into the rotation. Now consider this for a moment. The
airspeed difference in this airplane between rotation speed at 20K lbs and
the max flap and gear speed is just 70 kts!!!! Think about that. 260 is the
gear and flap max on this airplane, and you have just rotated at 190. And
the airplane is ACCELLERATING like a bullet fired from a gun! You don’t have
much time.
The technique in these airplanes is this. You ease into the rotation gently.
The instant you have a positive rate of climb you cycle the gear first, then
immediately cycle the flaps to full up from the take off position. In real
life, in the T38, this is almost one fluid motion. You rotate, pin the nose
at climb attitude, and hit the gear and flaps…like NOW!!!
This explains the basics of a take off in a high performance jet like a T38
or an F104. The long and short of it is that you have to be ready and
prepared to act…. and act correctly and at the exact instant required.
Flying these airplanes isn’t a walk in the park!
The next thing you are faced with in the sim is establishing the correct
climb schedule for your high performance jet. This takes a bit of getting
used to, as it requires a prime ADI cue. What this means is that in
airplanes like the T38 or the 104, you can’t easily see the wings. You’re
way out there in front of everything. Ordinarily, in a light airplane, you
can eyeball the wings along with the instruments and what should be your
prime cue in establishing a climb attitude…. your nose attitude. In the high
performance jet, you can’t see the wings and the nose is going to be quite
high above the horizon. Your prime pitch instrument is your ADI in these
airplanes. You establish the climb with the ADI; the ASI; and the power. You
hold a sample pitch attitude on the ADI, say 30 degrees of positive pitch.
You PIN it there!! Now you back off the power to give you the climb schedule
IAS you want. In the case of the T38 in real life, it’s a 300kt climb
schedule until 10K and .80 mach after that as an example.
In the sim with your CS 104, you can establish any climb schedule you like.
(You can pretend you’re in a military climb corridor and go supersonic at
SL, then let it out to 1.4 at 10K, 1.6 at 20K, and 1.8mach at 30K feet. From
35K to 60K, you can go all the way out to mach 2.0. Just be glad you’re not
paying for the fuel!! J
General Flight Characteristics of High Performance Jets In Turns
Let me say a few words about turns in delta wing and modified delta wing
plan form high performance jets.
First of all, in the T38, you can fly the airplane all day long without
touching the rudder. The airplane will do rolls all day long with just
aileron alone. The roll rate is so fast in these airplanes that adverse yaw
isn’t really an issue if the speed is high enough. At .9 mach the T38 is
restricted to ¾ stick travel to keep the roll rate DOWN, as coupling becomes
an issue at higher mach numbers!!!
Now, about turns. Anytime you enter a turn in a high performance jet like
these airplanes, you will immediately start picking up a huge drag index.
They bleed Ps, (energy) like a stuck pig at speeds below corner velocity
(another tutorial J) . What this means basically, is that you can expect
loss of airspeed and altitude in turns in these airplanes. You can
compensate for this with power, which is the way it’s done. Just be aware of
this basic fact of aerodynamics. The sim flight models on these airplanes
are quite good, and at low altitude especially, you have to be VERY careful
making turns at low airspeed. If you’re not sharp and catch it, you can be
bitten quickly with an increasing sink rate that might, if left alone for
too long, be unrecoverable!! Just be aware. Carry some speed into your
turns, and be ready with some power to hold altitude if desired.
Now for the meat of the subject…. landing a high performance jet!
I think Captain Sim got about a thousand emails from customers who were
complaining about the landing qualities of the F104. I can tell you there
never was anything wrong with the landing qualities. The sim pilots were
trying to land the 104 the same way they landed other airplanes, and believe
me, that won’t work! To get one of these fast jets down in one piece
requires some thinking…. some planning…. and a good dose of pure flying
technique.
It’s not the easiest thing in the world to do, but knowing it CAN be done if
done properly, should be like waving a red flag in front of a bull to those
of you I know in the sim community who love a challenge!
Let’s look at the problem for a moment and learn a few things about these
airplanes in the landing configuration.
First of all, in the case of the T38 and the 104, these aircraft are what we
call in the business “fuselage loaded”. What this means in short terms is
that the fuselage is a whole lot longer than the wings. This in turn
translates into a whole new way of doing things aerodynamically. Add to this
the fact that those little wings out there are not high lift wings at all,
but rather wings that require a lot of speed to create the lift required for
that long fuselage, and you have the makings of a high speed bullet to
control in flight that’s going to handle a whole lot differently than your
garden variety airplane with a balanced mass loading between the fuselage
and wings.
These airplanes require a whole new look into handling if they are going to
be flown correctly.
OK, let’s land a T38 Talon. If you can land this airplane, you can land the
CS F104, a Mig, a Tornado, or whatever other high performance jet you happen
to like to fly in the simulator.
The T38 lands fast, and those wings out there don’t hold it up very well if
you let the speed get out of hand. The secret is WING MANAGEMENT!
The first thing we want to take a long hard look at is the old adage that
pitch controls airspeed and throttle controls altitude. This is fine, and it
works, but in high performance airplanes on final approach, it’s better to
start thinking in terms of wing management instead of” this does this and
that does that”.
In other words, if you make a pitch change, you will need a power change…if
you make a power change…. you will need to make a pitch change. Power and
pitch are permanently married together, and in the high performance jet, it’s
good to think of them this way. In an airplane like an F104 on final, you’re
literally pointing the airplane while maintaining a proper sink rate. You do
this by managing either angle of attack or by flying the approach at a
computed airspeed for the landing GW and controlling everything by trading
off power and pitch as if they were ONE PARAMETER to control.
In these airplanes, you are entering into the world of ENERGY MANAGEMENT,
and you have to leave the old rules for the Cessna back in the locker room!
What we have to do on approach is NAIL a specific airspeed while maintaining
a sink rate that will put us through an imaginary window right at the runway
threshold.
In a high performance jet, this is done several ways. In the T38, we can use
angle of attack, which for an optimum approach in this airplane is .6 or an
indexer on speed. What the indexer does is pin the airplane at an OPTIMUM
angle of attack if we keep the airplane on the indexer donut. If we do this,
the angle of attack will automatically adjust the airplane to an airspeed
correction for the gross weight.
We can also do this manually, by using a known datum landing speed for a
known GW and adjusting that speed to reflect our ACTUAL landing weight,
which means we have to add the fuel weight and couple that to a new adjusted
airspeed based on the actual weight.
In the T38 for example, we can fly the indexer, or we can compute our
landing airspeed by taking 155kts and adding 1 kt per 100 lbs of fuel over a
base of 1000 lbs remaining.
In other words, when landing a high performance jet, you will have a higher
landing speed for a higher gross weight, and if you don’t compute the
landing speed for your fuel remaining, YOU WILL BE TOO SLOW ON FINAL!!! This
was what was causing the crashes for the Captain Sim F104 pilots…this and
trying to flare the airplane improperly.
Let’s land a high performance jet and see how it’s done shall we?
First of all, it’s CRITICAL that you plan the approach properly by computing
the required runway for the GW at touchdown and computing the final approach
speed for your GW if no angle of attack indexer is involved. Just FYI, most
modern day high performance jets use AOA for primary wing management on
final approach. For the older jets, you sometimes have AOA capability and
sometimes you don’t, depending on the airplane. If you have it, find out the
optimum AOA for approach and control that with pitch. That will
automatically put the airplane at the right airspeed for whatever the GW
happens to be on THAT approach.
The T38 I flew had an indexer. Flying the approach with a green donut was
the way to land this airplane. If no indexer, you landed the T38 at 155kts
plus fuel. This meant adding 1kt for every 100lbs of fuel you were carrying
into the approach over 1000 lbs.
Assuming you don’t have AOA capability in your simulator jet, make sure you
have the right required airspeed calculated for your fuel weight before
attempting to land the airplane or you will be way too slow on final. Get it
right and you are just beginning to understand what you have to do to land a
high performance jet like the CS F104.
OK, you have the fuel calculated and your GW has produced for you a revised
approach speed for your CS F104. You know all about the high drag in turns
for a low aspect ratio wing, and you’re going to attempt to land the F104.
Plan the approach so that you will have a fairly long final. I say this
because having the airplane stabilized on final in airspeed and sink rate is
absolutely CRITICAL for a successful landing. Anything less will get you
that “crash sign” every time!!
Let’s talk a bit about how to control airspeed and descent rate in these
airplanes, because it’s a bit different than doing it in say a Cessna or a
Piper.
What you have under you on final in one of these machines is literally a
rocket sled. It’s touchy, it’s extremely fast on approach, and it literally
WANTS to bite you. It demands your complete attention constantly.
Ordinarily, in your garden variety Cessna, you would control airspeed with
pitch and altitude with power, flying the approach adjusting these things to
maintain the approach profile. This is fine, and is in fact accepted
procedure for flying an approach.
With an airplane like the F104 however, the approach speed is so fast, and
the lift available on those tiny wings so little, that you literally don’t
have time to solve the intermesh equation that results from correcting using
the altitude/airspeed method INDIVIDUALLY. It still exists, but now you have
to consider that every time you correct in pitch, you will need an airspeed
correction, and every time you correct with power, you will need to correct
in pitch. These two factors have always been linked together, but in the
Cessna, you have had time to treat them individually. In something flying
final approach at up to 200kts, you have to begin to visualize the
altitude/airspeed thing as ONE CONTINIOUS CORRECTION! In other words, these
airplanes are on approach so fast, and are so heavy, and are so
aerodynamically sensitive in both pitch and power, that MINUTE correction
that considers BOTH these factors together is the way to handle the
situation.
Now, how to do that? It’s actually simple if you understand a few basic
things. What you do in POINT the airplane at a spot directly in front and
before the runway threshold and MONITOR the POWER! In these airplanes you
can expect to be carrying up to 90% power on approach under certain
conditions of GW. There’s no such thing as a power off glide approach in
these aircraft. The sink rates without power simply won’t permit it. In
fact, under certain conditions, the backside of the power curve won’t permit
it either. You can mismanage power and develop a sink rate in these
airplanes that can’t be recovered before ground contact.
In the CS F104 for example, use the airspeed bug on the HUD. Set it up for
your approach airspeed based on your GW/fuel calculation for final, then
point the dot in the center of the range circle right at the spot where you
will be flaring the airplane. (NOT where you will be landing the airplane!!)
Set up that long final by slowing to 240kts, drop the gear and flaps, then
begin trimming the airplane for your final approach speed. If that speed is
say 190kts, point the airplane at the runway and begin settling it down with
the airspeed bug right on the mark for 190kts.
The secret is keeping the speed on the bug mark with extremely sensitive
throttle adjustments and playing the sink rate at the same time. Learn to
think of an altitude or airspeed correction TOGETHER as each one effects the
other. If you are low and on speed, raising the nose will lower the
airspeed, so EXPECT to correct with throttle. IF you are high and fast, use
an energy method to correct. Lower the nose for the altitude correction
while watching the airspeed. EXPECT a throttle reduction back to the bug
marker. If you are high and slow, use energy again by lowering the nose back
to the spot and EXPECT an airspeed increase toward the bug mark.
The trick in landing these airplanes is to treat airspeed and altitude
control on final as ONE CONDITION, adjusting constantly in pitch to hold the
spot, and adjusting constantly with throttle to maintain the approach
airspeed. It’s the energy solution, and amounts to nothing more than a
constant correction back to the established datum through a thorough
understanding of how to manage the wing through pitch and power control..
You are treating the altitude/airspeed equation as ONE ENTITY in these
airplanes. In short, you have left the learning curve and must now adjust to
handling the landing situation as one problem, not two. You have married
airspeed and sink rate together as one problem to be solved through minimum
correction necessary; the goal being to put the airplane through a flare
window at exactly the right spot in the sky, at exactly the right airspeed
for the GW, and at exactly the flare point you need to land the airplane.
OK, you have controlled everything correctly and are now at that all
important point in space where you have to transition the high performance
jet to a landing attitude and put it on the ground without breaking it.
Let me be perfectly clear on one thing. You can reach this spot after having
done everything exactly right, then blow the landing in the blink of an eye
by screwing it up here.
This is where you put to use all that you have learned about landing this
airplane.
First of all, visualize the airplane in profile. The F104…and indeed the T38
as well, are very LONG airplanes. That nose gear sits WAY out in front of
the mains. This is what we mean when we talk about fuselage-loaded
airplanes.
Just looking at an F104 should tell you that you shouldn’t be able to land
this airplane in a deep flare, or anywhere near a stall. The aircraft is
just too long and fast and heavy for that. There is a “window” for these
airplanes on touchdown that allows main gear contact without a tail strike,
and that point is with the nose wheel just a bit high at touchdown.
The point I’m making here is that you land these airplanes under power, in a
controlled sink rate, and fairly FLAT as opposed to a conventional aircraft,
even one with a nose wheel!!!
So here you are, over the threshold with all the numbers intact. Now what?
Well, you begin a flare….but it’s a different kind of flare than you might
have been used to. Instead of a normal landing flare, you simply begin the
process of breaking the sink rate prior to touchdown. What you want to do
with a fuselage loaded fighter is control the sink rate by REDUCING IT to
produce a touchdown under control with the nose wheel just a bit off the
ground.
You do this by increasing the pitch to that landing attitude that gives you
this, then anticipating an airspeed decrease due to increasing drag that
will increase your sink rate.
This is the equation you have to master to land one of these airplanes. You
touch down with the nose wheel a bit high while controlling the increasing
sink rate due to drag with power. I can tell you that the F104 with landing
flaps down will develop a huge drag index the instant you begin to break
into the flare with increasing pitch. You MUST be ready for this…PERIOD!! As
you see the sink increase, expect a power increase into the touchdown. As
the mains make contact, stopcock the throttle; hit drag chute and FLY THE
AIRPLANE!!! Always….FLY THE AIRPLANE!!!
Congratulations. You’re down!
I sincerely hope this tutorial from real life serves to help those of you
who have already purchased and are considering purchasing these marvelous
high performance airplanes made available to you through the fantastic
programming now available to software developers working with MSFS.
Thank you, and happy flying J
Dudley Henriques
International Fighter Pilots Fellowship
Handling A High Performance Jet
Tutorial By Dudley Henriques
International Fighter Pilots Fellowship
As you know, from time to time, I will take a subject that comprises some
degree of bulk of my weekly email from sim enthusiasts and write a general
tutorial on that subject.
Much of the email I get is from sim pilots flying light airplanes asking me
for tips on how to fly the high performance military jets.
MS, in their infinite wisdom, has created a program for us that anyone can
enjoy according to individual tastes. You can fly a J3 Cub and relax and
watch the scenery. You can load up a DC10 or a 747 and fly the ocean with a
load of passengers. And, for the adventurous among us, you can also attempt
to fly the world’s most high performance aircraft. Since my background in
aviation is associated with flying and testing high performance airplanes
both prop and jet, I have spent a lot of time with developers helping to
create accurate flight modeling and enjoying as well having these airplanes
on the simulator. By providing this tutorial for you, it is my hope that you
might enjoy the world of high performance jets a little more.
For those of you who have learned to fly with MSFS using a light General
Aviation airplane like a 172, there might be some transitional problems when
you first attempt to fly a very high performance jet. There are very
distinct differences in the way these airplanes have to be handled in real
life, and this flows over into MSFS as well, if the flight modeling is
accurate, and I’m here to tell you that for the jets I have on the
simulator, the flight modeling is extremely accurately duplicated.
Many of the world’s finest aircraft are now becoming available for insertion
into MSFS, and the market for these aircraft among flight simulator
enthusiasts is growing by leaps and bounds. The realism available to
developers at this point in time for recreating accurate flight modeling for
these aircraft is astounding, and I’ve discovered through testing some of
these products for developers, that what they are creating in graphic detail
and flight modeling in their presentation to the end user that presents the
performance of the actual aircraft is almost beyond belief to me as a pilot
who has flown some of these airplanes during my career.
Considering this, it has occurred to me that those of you purchasing these
marvelous jets might appreciate a few “tips from the perch” so to speak. I’d
like to give you a “head’s up” if I can, on some of the things you will find
different in the way these aircraft should be flown in the simulator, as
opposed to the light aircraft you might have learned to fly in the
simulator, so that you might enjoy the experience a bit more, (and hopefully
crash a bit less enjoying that experience J
Much of my real world experience in high performance jets involved
flight-test in the Northrop T38 Talon, which is incidentally the perfect
aircraft to use as a real world example for you on how to fly a high
performance jet.
Although there are many…many, fine examples of high performance jets
available for your use in MSFS, I have chosen to profile one that I happen
to believe are among the best available to use as examples in this tutorial;
the Captain Sim F104. (And NO, I don’t work for Captain Sim J)
I’ll give you some general information from my real world experience in the
T38, and project that into the F104 in the sim. This will give you a fairly
good look at the handling required for high performance airplanes in a delta
and modified delta low aspect ratio configuration that have high mass
fuselage loading, which is critical for you to understand if you are to
enjoy flying these aircraft in the simulator.
The reason the T38 is perfect as a real world example is that this airplane
was designed specifically to display the same handling qualities found in
much higher performance airplanes…. and trust me, the T38 Talon is a VERY
high performance airplane..
The word with the Talon among those of us who flew this wonderful aircraft
was that if you could fly the T38 well, you wouldn’t have any problems
transitioning into the more powerful jets. I can tell you this is true. The
T38 has the same fuselage loaded mass ratio (much longer fuselage to wing
ratio) that is found in airplanes like the F104, where fuselage length as
opposed to wing area dictate extremely careful and delicate handling in
flight, especially in the left corner of the envelope at or near the
aerodynamic limit line where departure and high sink rate are the result of
inattention to wing management, and the power curve can go back side in the
blink of an eye..
Ok…what do you have to know to fly one of these beasts without bending it…or
in your case…getting that God awful “you crashed” screen after sitting there
thinking you were right on the money using the old Cessna 172 techniques!!!?
First of all, right out of the box, you have to relearn some of what you
might have been doing with some of the other airplanes in the sim; not that
what you have been doing is necessarily wrong mind you, but what you have to
learn to do NOW to fly THIS airplane, might need a bit of “adjusting in
procedure”
Let’s take one of the highest performance jet fighters ever developed for
MSFS and learn a thing or two about how to handle it without bending any
sheet aluminum. The Captain Sim F104 Starfighter is handled much like the
T38 believe it or not. It’s just faster and heavier. The aerodynamics
involved and handling technique for the 38 is quite similar to the 104.
I believe by using the 104 for the sim example and the T38 for a real life
comparison, I can get many of you to where you can handle a hot fighter
fairly well.
First of all, let’s talk about throttle use for a moment.
In a light piston powered airplane, when you feed in power, you get fairly
fast response. The airplane reacts to your throttle input almost
immediately. Not so in a high performance jet.
The first thing you learn when checking out in airplanes like these is that
what the engine and the airplane do will occur AFTER you use the throttle.
What this means literally is that when flying these airplanes, you have to
be able to PROJECT mentally well ahead of what you want the airplane to do.
In aircraft like the T38 and the F104, you are ALWAYS well ahead of the
airplane throttle wise. The aircraft will do what you have projected it must
do, seconds AFTER you have applied the power to make that happen!
This becomes a real consideration on take offs and landings in these
airplanes, because it’s here you are the most vulnerable to mistakes, and
you don’t make mistakes in these airplanes in real life without severe
penalty, and if the programming for your sim aircraft is even close to being
accurate, you won’t get a second chance on your screen either!! J
The theory is of course simple, and most of you already know about thrust
lag in turbojet engines. The trick is in learning to apply what you know in
theory to practice, and this is the key here…PRACTICE! Practice allows you
to become PREPARED, and PREPARED is the key word to learn in flying a high
performance jet.
Proper throttle use in high performance jets begins the instant you touch
the power to move the airplane on the ground after starting the engine. Rule
one. NEVER pivot an airplane on the inside strut when you turn while
taxiing. Apply enough power to establish forward motion, THEN TURN! Rule
two. Apply just enough power to begin motion, and then back off the
throttle. Use as little power as is necessary to actually taxi the aircraft
and not a one % more. Brace your hand on the throttle base and use that as a
fulcrum to allow you to use your wrist in making extremely small power
adjustments while taxiing. This practice will come in handy later on when
you are on final and need very small increments of power for very small
changes in the approach profile.
OK…so we know that the airplane will always be behind the power, and we will
always have to be in front of the power!!
Takeoffs!
At first, doing a takeoff in a high performance jet seems simple enough. You
cram in the power, rotate at the right speed, and off you go. But wait a
second. To do it RIGHT, is to understand completely the differences between
a high performance jet takeoff and a light plane take off. Not only will
things be happening at a faster rate, but also now you have CRITICAL NUMBERS
to consider.
Remember this next sentence and don’t forget it. In the high performance
jet; on take off, you will be accelerating right through the rotation and
beyond. This means that you will have to BEAT the maximum numbers for
several high-end parameters that will be occurring extremely fast.
Hesitation, or missing those high-end parameters could mean overstressing
the airplane’s parts!!!
Just to give you some idea of what’s involved here, in real life, on the
take off run, you will have a max tire speed; max nose wheel on the runway
speed, a rotation speed for the gross weight, and a gear up/flaps up max
parameter speed that will be occurring extremely close to your rotation
speed!!!!! Take off in a high performance jet is no place to be caught
sleeping! You have to be sharp. You have to be quick, and you have to be
right.
First of all, in the simulator, some programs might allow you to compute a
take off distance required and some might not. Study your airplane’s takeoff
weight vs. runway length carefully if the information is available. Make
sure you have enough runway going out, and coming back in. If this
information isn’t available, I’d suggest a minimum of 8000 feet of runway to
play with these airplanes. That’s the figure for the Talon, and the 104
lands even faster than this. Considering gross weight and/or fuel on board,
the 104 can have a landing speed of 200 kts! Think about that for a second.
A 172’s Vmax is slower than this…174mph. Your F104 at 16K lbs will LAND at
this speed. Heavier, and it lands much faster then the 172 can FLY!
Obviously, the F104 is going to require your “undivided attention” J
Back to take offs;
In a light airplane, you accelerate to a rotation speed and take off. That
speed is very close to the Vy or Vx for that light airplane, and you
establish the right nose attitude immediately and configure for a normal
climb. In other words, in these lighter airplanes, you are basically stable
in climb fairly quickly after rotation. Not so in the high performance jet.
These airplanes rotate while in severe acceleration, and that acceleration
CONTINUES through rotation and into the climb. In real life we have a max
tire speed. Let me give you an example of how critical the rotation can be
in the T38 Talon, and you can compare this to your general aviation light
airplane.
On takeoff, you release brakes, go to max throttle (full AB) and immediately
watch for the burner light within 5 seconds. If no light, you abort
immediately. Assuming you get the AB light off, you’re immediately checking
the nozzles for opening, and the fuel flow. If everything is normal there,
you’re off to the races.
Now here is where the real difference begins. At 130kts, you initiate
backpressure and lift the nose wheel at 140kts. At 155kts you rotate the
airplane. While you’re doing all this, keep in mind the max tire speed for
the nose wheel on the runway is 174kts. J
Now keep in mind the aircraft is accelerating all through this rotation and
that THIS is what’s really different from flying a light airplane. It
basically means that instead of having all day to raise the gear, you have
SECONDS before you reach the max gear speed of 240kts and tear the gear and
doors off the airplane. Also, if you’ve used 60% flaps for takeoff, they
also have to be retracted before 240 kts. In other words, in a high
performance jet like the T38 or the F104, you are pretty busy cleaning up
the airplane at rotation, then pretty busy again establishing the correct
climb attitude, which in a T38, gives you 300kts initially.
The CS F104 on takeoff in the sim requires some pretty fast technique at
rotation to get it right. It’s important in the sim as it is in real life to
check your take off gross weights and configurations for the proper rotation
speeds and runway length. Just be thankful you don’t have to check the
density and temperature as well J
For a clean F104 at 20K lbs, you accelerate the airplane to 190 kts for
rotation. You make the run as you do in all high performance jets. You raise
the nose wheel about 5 degrees and no more until you rotate. In a real
airplane, getting the nose too high on take off can take you deep into drag
rise…in fact, so deep in some airplanes that the takeoff can’t be
accomplished. So you want just a bit of bite on that low aspect wing out
there. But not too much.
The rotation problem in these airplanes can be demonstrated with the CS 104.
At 190kts, you EASE into the rotation. Now consider this for a moment. The
airspeed difference in this airplane between rotation speed at 20K lbs and
the max flap and gear speed is just 70 kts!!!! Think about that. 260 is the
gear and flap max on this airplane, and you have just rotated at 190. And
the airplane is ACCELLERATING like a bullet fired from a gun! You don’t have
much time.
The technique in these airplanes is this. You ease into the rotation gently.
The instant you have a positive rate of climb you cycle the gear first, then
immediately cycle the flaps to full up from the take off position. In real
life, in the T38, this is almost one fluid motion. You rotate, pin the nose
at climb attitude, and hit the gear and flaps…like NOW!!!
This explains the basics of a take off in a high performance jet like a T38
or an F104. The long and short of it is that you have to be ready and
prepared to act…. and act correctly and at the exact instant required.
Flying these airplanes isn’t a walk in the park!
The next thing you are faced with in the sim is establishing the correct
climb schedule for your high performance jet. This takes a bit of getting
used to, as it requires a prime ADI cue. What this means is that in
airplanes like the T38 or the 104, you can’t easily see the wings. You’re
way out there in front of everything. Ordinarily, in a light airplane, you
can eyeball the wings along with the instruments and what should be your
prime cue in establishing a climb attitude…. your nose attitude. In the high
performance jet, you can’t see the wings and the nose is going to be quite
high above the horizon. Your prime pitch instrument is your ADI in these
airplanes. You establish the climb with the ADI; the ASI; and the power. You
hold a sample pitch attitude on the ADI, say 30 degrees of positive pitch.
You PIN it there!! Now you back off the power to give you the climb schedule
IAS you want. In the case of the T38 in real life, it’s a 300kt climb
schedule until 10K and .80 mach after that as an example.
In the sim with your CS 104, you can establish any climb schedule you like.
(You can pretend you’re in a military climb corridor and go supersonic at
SL, then let it out to 1.4 at 10K, 1.6 at 20K, and 1.8mach at 30K feet. From
35K to 60K, you can go all the way out to mach 2.0. Just be glad you’re not
paying for the fuel!! J
General Flight Characteristics of High Performance Jets In Turns
Let me say a few words about turns in delta wing and modified delta wing
plan form high performance jets.
First of all, in the T38, you can fly the airplane all day long without
touching the rudder. The airplane will do rolls all day long with just
aileron alone. The roll rate is so fast in these airplanes that adverse yaw
isn’t really an issue if the speed is high enough. At .9 mach the T38 is
restricted to ¾ stick travel to keep the roll rate DOWN, as coupling becomes
an issue at higher mach numbers!!!
Now, about turns. Anytime you enter a turn in a high performance jet like
these airplanes, you will immediately start picking up a huge drag index.
They bleed Ps, (energy) like a stuck pig at speeds below corner velocity
(another tutorial J) . What this means basically, is that you can expect
loss of airspeed and altitude in turns in these airplanes. You can
compensate for this with power, which is the way it’s done. Just be aware of
this basic fact of aerodynamics. The sim flight models on these airplanes
are quite good, and at low altitude especially, you have to be VERY careful
making turns at low airspeed. If you’re not sharp and catch it, you can be
bitten quickly with an increasing sink rate that might, if left alone for
too long, be unrecoverable!! Just be aware. Carry some speed into your
turns, and be ready with some power to hold altitude if desired.
Now for the meat of the subject…. landing a high performance jet!
I think Captain Sim got about a thousand emails from customers who were
complaining about the landing qualities of the F104. I can tell you there
never was anything wrong with the landing qualities. The sim pilots were
trying to land the 104 the same way they landed other airplanes, and believe
me, that won’t work! To get one of these fast jets down in one piece
requires some thinking…. some planning…. and a good dose of pure flying
technique.
It’s not the easiest thing in the world to do, but knowing it CAN be done if
done properly, should be like waving a red flag in front of a bull to those
of you I know in the sim community who love a challenge!
Let’s look at the problem for a moment and learn a few things about these
airplanes in the landing configuration.
First of all, in the case of the T38 and the 104, these aircraft are what we
call in the business “fuselage loaded”. What this means in short terms is
that the fuselage is a whole lot longer than the wings. This in turn
translates into a whole new way of doing things aerodynamically. Add to this
the fact that those little wings out there are not high lift wings at all,
but rather wings that require a lot of speed to create the lift required for
that long fuselage, and you have the makings of a high speed bullet to
control in flight that’s going to handle a whole lot differently than your
garden variety airplane with a balanced mass loading between the fuselage
and wings.
These airplanes require a whole new look into handling if they are going to
be flown correctly.
OK, let’s land a T38 Talon. If you can land this airplane, you can land the
CS F104, a Mig, a Tornado, or whatever other high performance jet you happen
to like to fly in the simulator.
The T38 lands fast, and those wings out there don’t hold it up very well if
you let the speed get out of hand. The secret is WING MANAGEMENT!
The first thing we want to take a long hard look at is the old adage that
pitch controls airspeed and throttle controls altitude. This is fine, and it
works, but in high performance airplanes on final approach, it’s better to
start thinking in terms of wing management instead of” this does this and
that does that”.
In other words, if you make a pitch change, you will need a power change…if
you make a power change…. you will need to make a pitch change. Power and
pitch are permanently married together, and in the high performance jet, it’s
good to think of them this way. In an airplane like an F104 on final, you’re
literally pointing the airplane while maintaining a proper sink rate. You do
this by managing either angle of attack or by flying the approach at a
computed airspeed for the landing GW and controlling everything by trading
off power and pitch as if they were ONE PARAMETER to control.
In these airplanes, you are entering into the world of ENERGY MANAGEMENT,
and you have to leave the old rules for the Cessna back in the locker room!
What we have to do on approach is NAIL a specific airspeed while maintaining
a sink rate that will put us through an imaginary window right at the runway
threshold.
In a high performance jet, this is done several ways. In the T38, we can use
angle of attack, which for an optimum approach in this airplane is .6 or an
indexer on speed. What the indexer does is pin the airplane at an OPTIMUM
angle of attack if we keep the airplane on the indexer donut. If we do this,
the angle of attack will automatically adjust the airplane to an airspeed
correction for the gross weight.
We can also do this manually, by using a known datum landing speed for a
known GW and adjusting that speed to reflect our ACTUAL landing weight,
which means we have to add the fuel weight and couple that to a new adjusted
airspeed based on the actual weight.
In the T38 for example, we can fly the indexer, or we can compute our
landing airspeed by taking 155kts and adding 1 kt per 100 lbs of fuel over a
base of 1000 lbs remaining.
In other words, when landing a high performance jet, you will have a higher
landing speed for a higher gross weight, and if you don’t compute the
landing speed for your fuel remaining, YOU WILL BE TOO SLOW ON FINAL!!! This
was what was causing the crashes for the Captain Sim F104 pilots…this and
trying to flare the airplane improperly.
Let’s land a high performance jet and see how it’s done shall we?
First of all, it’s CRITICAL that you plan the approach properly by computing
the required runway for the GW at touchdown and computing the final approach
speed for your GW if no angle of attack indexer is involved. Just FYI, most
modern day high performance jets use AOA for primary wing management on
final approach. For the older jets, you sometimes have AOA capability and
sometimes you don’t, depending on the airplane. If you have it, find out the
optimum AOA for approach and control that with pitch. That will
automatically put the airplane at the right airspeed for whatever the GW
happens to be on THAT approach.
The T38 I flew had an indexer. Flying the approach with a green donut was
the way to land this airplane. If no indexer, you landed the T38 at 155kts
plus fuel. This meant adding 1kt for every 100lbs of fuel you were carrying
into the approach over 1000 lbs.
Assuming you don’t have AOA capability in your simulator jet, make sure you
have the right required airspeed calculated for your fuel weight before
attempting to land the airplane or you will be way too slow on final. Get it
right and you are just beginning to understand what you have to do to land a
high performance jet like the CS F104.
OK, you have the fuel calculated and your GW has produced for you a revised
approach speed for your CS F104. You know all about the high drag in turns
for a low aspect ratio wing, and you’re going to attempt to land the F104.
Plan the approach so that you will have a fairly long final. I say this
because having the airplane stabilized on final in airspeed and sink rate is
absolutely CRITICAL for a successful landing. Anything less will get you
that “crash sign” every time!!
Let’s talk a bit about how to control airspeed and descent rate in these
airplanes, because it’s a bit different than doing it in say a Cessna or a
Piper.
What you have under you on final in one of these machines is literally a
rocket sled. It’s touchy, it’s extremely fast on approach, and it literally
WANTS to bite you. It demands your complete attention constantly.
Ordinarily, in your garden variety Cessna, you would control airspeed with
pitch and altitude with power, flying the approach adjusting these things to
maintain the approach profile. This is fine, and is in fact accepted
procedure for flying an approach.
With an airplane like the F104 however, the approach speed is so fast, and
the lift available on those tiny wings so little, that you literally don’t
have time to solve the intermesh equation that results from correcting using
the altitude/airspeed method INDIVIDUALLY. It still exists, but now you have
to consider that every time you correct in pitch, you will need an airspeed
correction, and every time you correct with power, you will need to correct
in pitch. These two factors have always been linked together, but in the
Cessna, you have had time to treat them individually. In something flying
final approach at up to 200kts, you have to begin to visualize the
altitude/airspeed thing as ONE CONTINIOUS CORRECTION! In other words, these
airplanes are on approach so fast, and are so heavy, and are so
aerodynamically sensitive in both pitch and power, that MINUTE correction
that considers BOTH these factors together is the way to handle the
situation.
Now, how to do that? It’s actually simple if you understand a few basic
things. What you do in POINT the airplane at a spot directly in front and
before the runway threshold and MONITOR the POWER! In these airplanes you
can expect to be carrying up to 90% power on approach under certain
conditions of GW. There’s no such thing as a power off glide approach in
these aircraft. The sink rates without power simply won’t permit it. In
fact, under certain conditions, the backside of the power curve won’t permit
it either. You can mismanage power and develop a sink rate in these
airplanes that can’t be recovered before ground contact.
In the CS F104 for example, use the airspeed bug on the HUD. Set it up for
your approach airspeed based on your GW/fuel calculation for final, then
point the dot in the center of the range circle right at the spot where you
will be flaring the airplane. (NOT where you will be landing the airplane!!)
Set up that long final by slowing to 240kts, drop the gear and flaps, then
begin trimming the airplane for your final approach speed. If that speed is
say 190kts, point the airplane at the runway and begin settling it down with
the airspeed bug right on the mark for 190kts.
The secret is keeping the speed on the bug mark with extremely sensitive
throttle adjustments and playing the sink rate at the same time. Learn to
think of an altitude or airspeed correction TOGETHER as each one effects the
other. If you are low and on speed, raising the nose will lower the
airspeed, so EXPECT to correct with throttle. IF you are high and fast, use
an energy method to correct. Lower the nose for the altitude correction
while watching the airspeed. EXPECT a throttle reduction back to the bug
marker. If you are high and slow, use energy again by lowering the nose back
to the spot and EXPECT an airspeed increase toward the bug mark.
The trick in landing these airplanes is to treat airspeed and altitude
control on final as ONE CONDITION, adjusting constantly in pitch to hold the
spot, and adjusting constantly with throttle to maintain the approach
airspeed. It’s the energy solution, and amounts to nothing more than a
constant correction back to the established datum through a thorough
understanding of how to manage the wing through pitch and power control..
You are treating the altitude/airspeed equation as ONE ENTITY in these
airplanes. In short, you have left the learning curve and must now adjust to
handling the landing situation as one problem, not two. You have married
airspeed and sink rate together as one problem to be solved through minimum
correction necessary; the goal being to put the airplane through a flare
window at exactly the right spot in the sky, at exactly the right airspeed
for the GW, and at exactly the flare point you need to land the airplane.
OK, you have controlled everything correctly and are now at that all
important point in space where you have to transition the high performance
jet to a landing attitude and put it on the ground without breaking it.
Let me be perfectly clear on one thing. You can reach this spot after having
done everything exactly right, then blow the landing in the blink of an eye
by screwing it up here.
This is where you put to use all that you have learned about landing this
airplane.
First of all, visualize the airplane in profile. The F104…and indeed the T38
as well, are very LONG airplanes. That nose gear sits WAY out in front of
the mains. This is what we mean when we talk about fuselage-loaded
airplanes.
Just looking at an F104 should tell you that you shouldn’t be able to land
this airplane in a deep flare, or anywhere near a stall. The aircraft is
just too long and fast and heavy for that. There is a “window” for these
airplanes on touchdown that allows main gear contact without a tail strike,
and that point is with the nose wheel just a bit high at touchdown.
The point I’m making here is that you land these airplanes under power, in a
controlled sink rate, and fairly FLAT as opposed to a conventional aircraft,
even one with a nose wheel!!!
So here you are, over the threshold with all the numbers intact. Now what?
Well, you begin a flare….but it’s a different kind of flare than you might
have been used to. Instead of a normal landing flare, you simply begin the
process of breaking the sink rate prior to touchdown. What you want to do
with a fuselage loaded fighter is control the sink rate by REDUCING IT to
produce a touchdown under control with the nose wheel just a bit off the
ground.
You do this by increasing the pitch to that landing attitude that gives you
this, then anticipating an airspeed decrease due to increasing drag that
will increase your sink rate.
This is the equation you have to master to land one of these airplanes. You
touch down with the nose wheel a bit high while controlling the increasing
sink rate due to drag with power. I can tell you that the F104 with landing
flaps down will develop a huge drag index the instant you begin to break
into the flare with increasing pitch. You MUST be ready for this…PERIOD!! As
you see the sink increase, expect a power increase into the touchdown. As
the mains make contact, stopcock the throttle; hit drag chute and FLY THE
AIRPLANE!!! Always….FLY THE AIRPLANE!!!
Congratulations. You’re down!
I sincerely hope this tutorial from real life serves to help those of you
who have already purchased and are considering purchasing these marvelous
high performance airplanes made available to you through the fantastic
programming now available to software developers working with MSFS.
Thank you, and happy flying J
Dudley Henriques
International Fighter Pilots Fellowship
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