F-14 Questions Answered - Ask Away

[Tomcatguy111]

So, first, let us talk about the “cheats”.

Turning the air source off, closed the bleed valves on the engines, And with the slightly higher pressure ratio that results, you should get a tiny increase in thrust. The guys who advocated this called it “zone six”. The problem, of course is that you also lose things like cabin pressurization and air conditioning, and weapon system cooling. So, while you might get a little bit more out of the motors, you’re hurting just about everything else on the airplane that you need, including crew.

Pulling breakers, LE1 and LE two locks out the aux flaps, and allows you to extend landing, flaps, while keeping the auxiliary flaps retracted.

Use of the landing flaps was a somewhat controversial topic in the F14 community.

The NATOPS extension speed limit on the landing flaps was 225 knots. Most squadrons had an SOP of 200 knots, to save wear and tear of flap/slat mechanisms, particularly the torque tubes that transmitted force from hydraulic motor to actuators. The torque tubes were a very high wear item, and were easily broken. In fact, it is reported, that the torque tubes were one of the first components that Iran had to reverse engineer.

So, why have a squadron SOP to save where and tear on flap parts, especially when you’re flying off the boat and normal flap extension and operation is critical for landing speed, only to tear them up by exceeding that speed limit while maneuvering the aircraft?

I’ve tried landing flaps - and in certain circumstances (flat scissor), they work. But in nearly every other maneuvering regime, you are asking to damage the airplane. For example, at the bottom of a rolling scissor, you’re gonna be about 300 kn. If you extended the landing flaps at the top of that scissor, you are more than doubling the design load on a component that was already known to be weak. I always knew when people came back from an ACM engagement with a flap slat lockout on landing, that they had been “cheating“. And not cheating particularly well, because they exceeded the speed limit of the airplane.

Breaking parts as a result.

Not a great plan.

So, no, I was not a fan of using landing flaps, even with LE1 and LE2 pulled. The only advantage to using full flaps with the aux flaps retracted, was that you get better airflow over the horizontal stabilizers, and perhaps a bit more pitch authority. But the disadvantage of LE1 and LE@ pulled, is that you can now sweep the wings with landing flaps extended, potentially crunching the main flaps into the side of the aircraft. Again, I just don’t think any of these “cheats” were a particularly smart idea.

There is no tactical advantage to the wing sweep switch in manual versus automatic. If the wing sweep switch is manual, and the wings are slightly aft of program, as soon as the air data computer starts to sweep the wings according to schedule, they go from manual to automatic and begin to program aft. You cannot move the wings farther forward than program, using the manual switch, you can only move them farther aft. So, what gain would you have?

Perhaps you referring to the use of the emergency wings, sweep handle, that allows you to position the wings wherever you want without regard to structural limits. Again, like the landing, flaps, exceeding the limits on the airplane is just not a great idea. In a high altitude fight, you could potentially push the wings forward, all the way to 20° where the program might have them say, 35°. So yes, you gained some performance, but you are exceeding a structural limit in the airplane. At some point exceeding structural limits is going to result in a damaged airplane.

Damaged airplanes don’t win fights.

Worse, I think that damaged airplanes are part of the reason that the F-14 was taken out of service. The maintenance man hour for every flight hour on the aircraft was considerably higher than that of the FA-18. Part of this was the normal process of airplanes getting older (the F/A-18C/D had really high maintenance man hours per flight hours in their later years of service) part of this was the overall complexity of the frame itself, but part of this was deliberately abusing the airplane.

For me, abusing the aircraft was the same thing as abusing the sailors who had to take care of it. If you “borrow the car“ and then tear it up and bring it back, they’re the poor souls who have to put it back together again. I fought the airplane to its limit, but I never exceeded the limit (OK, a little gentle exploration of speed and altitude may have happened, but not G, not flaps, and not air load limits) because I didn’t wanna break the thing and have our guys spend hundreds of hours putting it right.

More on the AIM-54 later. I’m not sure how much I can tell you that isn’t still classified.

Again thanks so much for the detailed replies. Just to clarify the wing sweep switch “cheat” was referencing an interview with a pilot who said that when he fought the airplane, he always kept the switch in manual. Can I assume you preferred auto? Also, can you comment on rudder usage? As I understand it rudders we’re not heavily taught at the RAG, but good drivers knew how to use them. How much did they help when fighting the jet?

 

[Astro14]

Again thanks so much for the detailed replies. Just to clarify the wing sweep switch “cheat” was referencing an interview with a pilot who said that when he fought the airplane, he always kept the switch in manual. Can I assume you preferred auto? Also, can you comment on rudder usage? As I understand it rudders we’re not heavily taught at the RAG, but good drivers knew how to use them. How much did they help when fighting the jet?

So, let’s start with the wing sweep question.

There’s a great deal to manage in an air combat engagement. You’re flying the airplane in three dimensions, keeping track of multiple bogies, and maneuvering the aircraft. You’re looking for, and an addition to flying the airplane, which includes stick throttle and rudders, you’re going through weapon select, radar modes, sidewinder acquisition, and everything else in order to get a weapon solution and shoot the adversary.

Why would I add one more thing to think about?

The wings were designed to work in auto. You cannot get a more optimum wing position for aircraft performance through the use of manual. You can only get a farther aft sweep. So, you cannot enhance the aircraft’s performance by flying the airplane around in manual wing sweep.

There is one exception - if you have unloaded (less than one G) - and you were beginning a “bug out“, then and only then, with sweeping the wings after program give you a very slight drag reduction and a very slight acceleration increase.

But I emphasize that it’s slight.

And in that moment, you are not focused on things like weapon, selection, or radar modes, because you are running away. And in that moment, if you wanted to select manual during the unload to try and improve your acceleration, and improve your chances of a successful disengagement.

OK, in that one instance, go ahead and sweep the wings manually.

 

[Astro14]

Now let’s talk rudder use.

Rudder is useful when the aircraft is slow. And by slow, I mean under 200 knots.

We do teach use of rudder in the RAG.

But we do not encourage students to get down to very low air speed, so the Flight Regime in which you would be using them is not a place in the envelope where we encourage students to go.

As they gain more familiarity with the aircraft, then yes, some slower speed maneuvering, for example, to get a shot, becomes appropriate.

Earlier on in this thread, I talked about maneuvering the airplane at very, very low air speed. I talked about the use of differential thrust.

It works well when you have the GE F-110 motors, but it does not work well with the TF 30s, pulling the throttle back in after burner when you’re near zero air speed is a great way to induce a compressor stall in that motor.

At that very low air speed, if I want the airplane to turn, say, left, then I will feed in left rudder while simultaneously applying right and forward stick.

Yes, we are talking about Cross controlling the aircraft completely. But at a very high AOA, in excess of 25°, in many airplanes you experience aileron reversal. In the F-14, without ailerons , similar effects take place and left spoiler and differential tail have the same effect as aileron reversal.

So, at those very high angles of attack, right stick means left roll and vice versa.

I talked about this when I discussed the stability augmentation system.

The difference between the F-14, and many of its contemporaries that were equipped, fly by wire, is that the F-14 required the pilot to manipulate the flights controls in a precise and purposeful way to control the airplane’s path.

In the F/A-18 for example, you simply slap the stick the direction you wanted to go, and the flight control computers (FCC) would figure out what surfaces to move. Those surfaces might be on the leading edge of the wing, the trailing edge of the wing, on the vertical tails, or on the horizontal tails. It all depends on the FCC program and the aircraft’s current airspeed and angle of attack.

All done by a computer, all calculated, based on laws and body rate sensors.

In the F-14, all of that awareness of angle of attack, airspeed, and subsequent computation, took place between the ears of the pilot.

 

[BMWTurboDzl]

@Astro14 Did you ever meet a F/A-18 pilot who earned his wings in the USAF first? I was chatting it up with a guy this past weekend who was retired (age 55 ish). He apparently spent 5 yrs in the USAF and then moved to the Navy. Some funny stories how he received a good razing as the "Air Force Guy" when it came to some of his water based certifications (ex, Parachuting into water, exiting an aircraft submerged in water, etc).

 

[Tomcatguy111]

Now let’s talk rudder use.

Rudder is useful when the aircraft is slow. And by slow, I mean under 200 knots.

We do teach use of rudder in the RAG.

But we do not encourage students to get down to very low air speed, so the Flight Regime in which you would be using them is not a place in the envelope where we encourage students to go.

As they gain more familiarity with the aircraft, then yes, some slower speed maneuvering, for example, to get a shot, becomes appropriate.

Earlier on in this thread, I talked about maneuvering the airplane at very, very low air speed. I talked about the use of differential thrust.

It works well when you have the GE F-110 motors, but it does not work well with the TF 30s, pulling the throttle back in after burner when you’re near zero air speed is a great way to induce a compressor stall in that motor.

At that very low air speed, if I want the airplane to turn, say, left, then I will feed in left rudder while simultaneously applying right and forward stick.

Yes, we are talking about Cross controlling the aircraft completely. But at a very high AOA, in excess of 25°, in many airplanes you experience aileron reversal. In the F-14, without ailerons , similar effects take place and left spoiler and differential tail have the same effect as aileron reversal.

So, at those very high angles of attack, right stick means left roll and vice versa.

I talked about this when I discussed the stability augmentation system.

The difference between the F-14, and many of its contemporaries that were equipped, fly by wire, is that the F-14 required the pilot to manipulate the flights controls in a precise and purposeful way to control the airplane’s path.

In the F/A-18 for example, you simply slap the stick the direction you wanted to go, and the flight control computers (FCC) would figure out what surfaces to move. Those surfaces might be on the leading edge of the wing, the trailing edge of the wing, on the vertical tails, or on the horizontal tails. It all depends on the FCC program and the aircraft’s current airspeed and angle of attack.

All done by a computer, all calculated, based on laws and body rate sensors.

In the F-14, all of that awareness of angle of attack, airspeed, and subsequent computation, took place between the ears of the pilot.

Thanks once again for the thoughtful and informative answer.

One other question I have is regarding the external fuel tanks. I’ve always been interested in those, because all the other teen series jets carried the standard “drop” tanks. The Tomcats tanks are unique and more of a conformal type designed to stay with the aircraft. I guess my question is how much the tanks affected the agility and flying qualities of the airplane? Most of the time when you see pics of jets doing any ACM/BFM training, FFARP, TOPGUN etc. external tanks are absent, therefore I assume some performance was gained without them. How much?

 

[y_p_w]

One other question I have is regarding the external fuel tanks. I’ve always been interested in those, because all the other teen series jets carried the standard “drop” tanks. The Tomcats tanks are unique and more of a conformal type designed to stay with the aircraft.

What? It had drop tanks. Apparently they decided it didn't need fins, but they could be jettisoned if needed.

 

[Pew]

It's been a couple years since I've read the entire thread so sorry if it was answered but @Astro14 what was the airplane(s) you guys were worried about tangling with, either via missiles or dogfighting, from our enemies at that time?

 

[Astro14]

It's been a couple years since I've read the entire thread so sorry if it was answered but @Astro14 what was the airplane(s) you guys were worried about tangling with, either via missiles or dogfighting, from our enemies at that time?

Any airplane, flown well, can be a threat.

In particular, though, the SU-27 was a formidable airplane. It carried the "long burn" version of the AA-10 which was a long range weapon. We had tactics, and some tech advantages, over those crews and airplanes, but the airframe and the missile were in the same league as our own, and we had to take them very seriously.

The MiG-29 was a formidable airplane, with great performance, and some multi-sensor capability, but was limited in range, had terrible cockpit ergonomics, and had the "short burn" AA-10s, so, again, a serious threat, but not invincible.

Even the lowly MiG-23, which had poor maneuverability, poor cockpit visibility, a lousy radar and poor weapons, but it had tremendous speed, and if you let him sneak up on you, he could kill you.

 

[y_p_w]

Former Tomcat pilot Mike “Thumper” Bonner talks about what made the F-14 so effective.



It’s this one, which apparently had only been used for test/evaluation before being used to train maintainers.

https://wingsmuseum.org/exhibits/grumman-f-14a-tomcat/

 

[Astro14]

I’ve seen that jet - it’s a good museum. Haven't been there in a couple of years, but may have to stop by next month when I am in Denver again.

I’ll give the video a watch when I get a chance.

Thanks!

 

[billt460]

Astro, does fuel burn in afterburner become a law of diminishing returns? By that I mean is the amount of thrust in direct proportion to the amount of fuel burned, as the pilot advances through all of the stages the afterburner provides?

Or does the fuel burn increase disproportionately with thrust, with more fuel consumed less efficiently, as the pilot gets into the highest range of burner?

What got me thinking about this is propellant in a rifle cartridge becomes less efficient the more you add to achieve more velocity in a given bore size. For example, in a cartridge like a .338 Win. Mag. a max load with a 250 grain bullet is around 68 to 75 grains of powder to achieve 2,700 FPS.

In a .338-378 Weatherby Magnum, it takes a max load of 95 to 107 grains of a similar burn rate propellant, to achieve just 100 FPS more with the exact same bullet, (2,800 FPS). So you're burning right around 30% more powder, (fuel), on the high end, to get only 100 FPS more velocity.

Do afterburners suffer a similar drop in efficiency?

 

[Astro14]

Astro, does fuel burn in afterburner become a law of diminishing returns? By that I mean is the amount of thrust in direct proportion to the amount of fuel burned, as the pilot advances through all of the stages the afterburner provides?

Or does the fuel burn increase disproportionately with thrust, with more fuel consumed less efficiently, as the pilot gets into the highest range of burner?

What got me thinking about this is propellant in a rifle cartridge becomes less efficient the more you add to achieve more velocity in a given bore size. For example, in a cartridge like a .338 Win. Mag. a max load with a 250 grain bullet is around 68 to 75 grains of powder to achieve 2,700 FPS.

In a .338-378 Weatherby Magnum, it takes a max load of 95 to 107 grains of a similar burn rate propellant, to achieve just 100 FPS more with the exact same bullet, (2,800 FPS). So you're burning right around 30% more powder, (fuel), on the high end, to get only 100 FPS more velocity.

Do afterburners suffer a similar drop in efficiency?

To an large extent, yes, it’s a decrease in efficiency as the amount of AB used goes up.

When looking at jet engines, the key parameter for comparison is thrust specific fuel consumption. That is: how much thrust do I get for each unit of fuel burned.

By normalizing it over the amount of thrust, you can look at the fuel burned, and get an idea of relative engine efficiency.

I don’t have the numbers for any of the engines I flew (TF-30, F-110, F-404) with afterburner, but even minimum AB would dramatically increase fuel consumption for each additional bit of thrust.

In this paper: https://www.icas.org/icas_archive/ICAS2008/PAPERS/286.PDF - which talks about the F-100 engine in the F-16 - TSFC is pretty linear across the basic engine RPM, so, as you increase power, you burn more fuel at about the same rate for each pound of thrust, and the TSFC is about 0.7.

But Min AB bumps that up over 1.0 and max AB takes it up to about 2.3.

So, yeah, you’re getting about a 50% thrust increase, but at about 4 times the fuel burned (in lbs/hour) over basic (unaugmented) thrust.

So, why use AB at all, if it costs that much in fuel?

Because the AB allows for a couple of things:
1. Supersonic flight due to increased exhaust velocity
2. A smaller engine during most of the flight, saving weight and fuel burn.
3. The ability to add a large amount thrust for a few critical minutes to win a fight.

In an airliner, AB doesn’t make much sense, with the huge fuel efficiency penalty for the increase in thrust, but item 1. Above, was critical to Concorde.

And the numbers are why Boom Supersonic, and other development companies, are looking at ways to get sufficient exhaust velocity without using an AB, so that the lbs of fuel/lb of thrust numbers are close to that of subsonic airliners.

 

[Nyati]

Do you know Jambo & Hollywood?

 

[Astro14]

Do you know Jambo & Hollywood?

Jambo doesn't ring a bell - but I do know a couple of guys with the callsign of "Hollywood".

 

[Nyati]

Jambo doesn't ring a bell - but I do know a couple of guys with the callsign of "Hollywood".

Jambo is a good friend of mine- was an instructor at Top Gun. He’s my hunting buddy. Every year at Veteran’s day his former Top Gun buddies meet in Texas to go pig hunting. They have some wild stories to tell. They’re all retired now.. Hollywoods last name is Dishart

 

[billt460]

Astro, when you started your Navy flying career, were F4 Phantom's still in the inventory?

 

[y_p_w]

Or does the fuel burn increase disproportionately with thrust, with more fuel consumed less efficiently, as the pilot gets into the highest range of burner?

I'm reading that at higher afterburner stages, it's more efficient at converting fuel to energy, but less efficient at converting energy to thrust.

 

[Astro14]

Astro, when you started your Navy flying career, were F4 Phantom's still in the inventory?

When I started, in 1986, there were still a couple of Phantom squadrons in the Navy.

By the time I was flying the F-14 they had all converted to the F-14, but there were still F-4s flying in the Air Force.

 

[MolaKule]

I'm reading that at higher afterburner stages, it's more efficient at converting fuel to energy, but less efficient at converting energy to thrust.

Thread 'MolaKule Q&A on Aircraft Structures III'

May 19, 2025

On most commercial aircraft, the engine is external and attached to the wing or fuselage.

What is the name of the structure that attaches the engine to the wing or fuselage?

• MolaKule
• Replies: 38
• Forum: Aviation

"...The increase in thrust is a function of the increase in jet pipe temperature as a result of afterburning. For a perfectly efficient system, the relationship between the temperature ratio before and after fuel is burnt, and the thrust increase is nearly linear in the typical operating range with temperature ratios of 1.4 to 2.2. Within this range we can expect a 40% increase in thrust for a doubling of the temperature in the jet pipe. Thus, if afterburning raises the jet pipe temperature from 700°C (973 K) to 1500°C (1773 K) this results in a thrust increase of around 36%..."

https://aerospaceengineeringblog.com/jet-engine-design-afterburning/#:~:text=Even though afterburning is incredibly fuel-inefficient, it is,low thrust configuration and a fuel-inefficient, high-thrust configuration.

and

https://www.sjsu.edu/ae/docs/project-thesis/Justin.Williams-F22.pdf

 

[Astro14]

Too funny not to share.



I can spare $6/month to rescue a helpless Tomcat and provide it with fuel, a hardened shelter, and love…

With Sarah Mclachlan singing that song how can you resist?