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westr

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Seen a good question and answer on quora.com and thought I would share.

 

In Top Gun it seems that every time an F-14 passes anywhere near another aircraft’s ‘jet-wash’ there was a huge risk of flame out. How accurate is that during ‘real life’ ACM?

John Chesire

John Chesire, TOPGUN graduate, and around when the movie was filmed.

Answered Oct 16 · Upvoted by Glenn Davis, former Boatswain's Mate 2nd Class at United States Navy (19… and Adrian Kruger, Qualified pilot with a PPL, student of all things Aviation.

TL;DR - Yes it was accurate.

 

While it might not have happened “every time” in real life it did happen far more than it ever should have. As explained by Jim Mowreader the early F-14A had a terrible engine to put into a fighter, the Pratt & Whitney TF30 fan engine. It was extremely susceptible to engine stalls and was thankfully replaced later by the far more applicable and rugged General Electric F110-GE-400 afterburning turbofans in later F-14 models.

 

I remember the first time a similar incident occurred in real life. On April 19, 1977 a pilot from VF-124 [Lt. G.A. ‘Bean” Barrett] was practicing the simulated “gunnery pattern” over the Salton Sea with several other F-14 aircraft in the pattern. While in the pattern Bean crossed the wake and jet wash of another F-14 in front of him. One or both of his engines stalled, and I believe he entered the dreaded, flat spin. Regardless the crew ejected safely. I remember everyone in F-14 training at the time was very disturbed by this incident. We were told the F-14 would not spin, and now we learned that was wrong.

 

(Talking to Adm. Pettigrew last year who was the technical advisor for the movie, he said Bean’s accident and another similar one led to that part of the movie script. Originally the scene was supposed to have been a mid-air collision but the Navy did not like that so they changed it to a flameout and a flat spin for the scene, which then was OK with the Navy.)

 

In the F-14A with that particular engine, almost any disturbed air entering it would often cause a compressor stall. Even without flying behind someone’s jet wash, the engine would often stall with a very hard turn at low airspeed and high angle of attack. It was not uncommon for me during a week of Air Combat Maneuvering (ACM) training to have a number of compressor stalls. Usually I was able to just clear them and resume, however sometimes to avoid “over-temping” the engine I had to shut it down. Of course sometimes, the engine just totally quit and shut down by itself at a high angle of attack.

 

That engine caused a number of flat spins. I lost a good friend, squadron mate, and RIO in one: Lt William (Bill) C. "Shadow" Matthews. The forward transverse G-forces made it unable in the flat spin to eject. Also the scene of Goose hitting the canopy was based on an actual incident, but I cannot remember who the RIO was.

 

Related: Top Navy plane found plagued with fatal spin F-14 design cure set at $78 million

 

[Note: While this article says the F-14 controls were a problem - which they were somewhat - the real problem was losing one engine while both were in full afterburner which happens. The great asymmetric yaw that resulted caused the aircraft to ‘couple-up’, depart controlled flight, and then go right into a flat spin.]

 

I would like to know if this is simulated in our F-14 sim with the F-14a if we were to be following closely behind another aircraft and get into its jetwash?

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We were told the F-14 would not spin, and now we learned that was wrong.

 

Ive read that with the wings swept that it wont spin. But i dont think this information was available in 1977. obviously low speed high AOA the wings are extended though. if it starts to spin in game, manually sweeping the wings should correct this, in theory :thumbup:

 

 

Also maybe some of the reason the B is being released first. shouldnt have to worry as much about it. the A will be the tough one to fly.


Edited by macidcrook

DCS WISHLIST: F4U-4, A-4M, A-1H(AD-6), OV-10A

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I’m looking forward to LGB’s with the B and was so glad and appreciative that HB are making it, but a large part of me can not wait for the A and all the quirks it will bring. Sounds like you will really need to manage her to get the best out of her. I remember reading an F-14 pilot describing that the F-14a could more or less do everything the B and D could do in ACM it was just a lot more difficult to do it. That special whining noise the TF-30s make as well, it just sounds like TOP GUN.

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I have to wonder why they made both versions? It seems if they put all the effort into the B version it might be done now.

We only got one version of the F/A-18 and nobody is complaining.

To a lot of people, the F-14A is the definitive Tomcat.

 

The 'A' wasn't just the variant featured in that ridiculous 80s movie about fictional trophies, Kenny Loggins and testosterone, it was the version that was out there defending the fleet from the late 1970s until the first 'B' 'Cats began to trickle in.

 

It was also the plane that a lot of us grew up seeing at airshows as well as the Naval Air Stations near our homes.

 

I guess you could say that, for all it's quirks and imperfections, modeling the first operational Tomcat is a form of wish fulfillment and nostalgia.

 

[shrug]

 

That was my take, anyway.

 

Sent from my SM-G930F using Tapatalk

Can't pretend fly as well as you can.

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The A seems like it will be even more interesting to fly anyway, given the temperamental nature of the TF-30s. Apparently the difference in flying performance is quite noticable between the 2 variants as well.

9./JG27

 

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Seen a good question and answer on quora.com and thought I would share.

 

In Top Gun it seems that every time an F-14 passes anywhere near another aircraft’s ‘jet-wash’ there was a huge risk of flame out. How accurate is that during ‘real life’ ACM?

John Chesire

John Chesire, TOPGUN graduate, and around when the movie was filmed.

Answered Oct 16 · Upvoted by Glenn Davis, former Boatswain's Mate 2nd Class at United States Navy (19… and Adrian Kruger, Qualified pilot with a PPL, student of all things Aviation.

TL;DR - Yes it was accurate.

 

While it might not have happened “every time” in real life it did happen far more than it ever should have. As explained by Jim Mowreader the early F-14A had a terrible engine to put into a fighter, the Pratt & Whitney TF30 fan engine. It was extremely susceptible to engine stalls and was thankfully replaced later by the far more applicable and rugged General Electric F110-GE-400 afterburning turbofans in later F-14 models.

 

I remember the first time a similar incident occurred in real life. On April 19, 1977 a pilot from VF-124 [Lt. G.A. ‘Bean” Barrett] was practicing the simulated “gunnery pattern” over the Salton Sea with several other F-14 aircraft in the pattern. While in the pattern Bean crossed the wake and jet wash of another F-14 in front of him. One or both of his engines stalled, and I believe he entered the dreaded, flat spin. Regardless the crew ejected safely. I remember everyone in F-14 training at the time was very disturbed by this incident. We were told the F-14 would not spin, and now we learned that was wrong.

 

(Talking to Adm. Pettigrew last year who was the technical advisor for the movie, he said Bean’s accident and another similar one led to that part of the movie script. Originally the scene was supposed to have been a mid-air collision but the Navy did not like that so they changed it to a flameout and a flat spin for the scene, which then was OK with the Navy.)

 

In the F-14A with that particular engine, almost any disturbed air entering it would often cause a compressor stall. Even without flying behind someone’s jet wash, the engine would often stall with a very hard turn at low airspeed and high angle of attack. It was not uncommon for me during a week of Air Combat Maneuvering (ACM) training to have a number of compressor stalls. Usually I was able to just clear them and resume, however sometimes to avoid “over-temping” the engine I had to shut it down. Of course sometimes, the engine just totally quit and shut down by itself at a high angle of attack.

 

That engine caused a number of flat spins. I lost a good friend, squadron mate, and RIO in one: Lt William (Bill) C. "Shadow" Matthews. The forward transverse G-forces made it unable in the flat spin to eject. Also the scene of Goose hitting the canopy was based on an actual incident, but I cannot remember who the RIO was.

 

Related: Top Navy plane found plagued with fatal spin F-14 design cure set at $78 million

 

[Note: While this article says the F-14 controls were a problem - which they were somewhat - the real problem was losing one engine while both were in full afterburner which happens. The great asymmetric yaw that resulted caused the aircraft to ‘couple-up’, depart controlled flight, and then go right into a flat spin.]

 

I would like to know if this is simulated in our F-14 sim with the F-14a if we were to be following closely behind another aircraft and get into its jetwash?

 

And other TOPGUN grads would tell you jet wash would never do that unless you were parked 10 feet behind a jet in afterburner and its blowing straight down your intake.

 

The jetwash in the movie was the there for the sole purpose of killing Goose, whose canopy impact in a flat spin was far more plausible than jetwash killing an engine. Would have been realistic if he threw the throttles around at high alpha while rolling...….instant spin.

 

repeat jetwash- especially from an F-5 or A-4 wont even make your Turkey hiccup. Though the engines are finicky- jet wash isn't gonna do it. It never happened in the fleet due to jetwash. Forget jetwash…...forever and ever and ever.

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To a lot of people, the F-14A is the definitive Tomcat.

 

The 'A' wasn't just the variant featured in that ridiculous 80s movie about fictional trophies, Kenny Loggins and testosterone, it was the version that was out there defending the fleet from the late 1970s until the first 'B' 'Cats began to trickle in.

 

It was also the plane that a lot of us grew up seeing at airshows as well as the Naval Air Stations near our homes.

 

I guess you could say that, for all it's quirks and imperfections, modeling the first operational Tomcat is a form of wish fulfillment and nostalgia.

 

[shrug]

 

That was my take, anyway.

 

Sent from my SM-G930F using Tapatalk

 

So, why not give us the A first? I'd be happy with just it. I've never been a fan of playing in the mud with fighters.

Buzz

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I think its good to have the A and B. It shows alot for the devs to spend the time to do both with pfm and sell them for the same price. It would be one thing to do one in pfm and the other not. It will be nice to fly them both and make an assessment on your own. All these modules have quirks and some people love them and others dont. Might as well get a broader market with 2 variations.

DCS WISHLIST: F4U-4, A-4M, A-1H(AD-6), OV-10A

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I have to wonder why they made both versions? It seems if they put all the effort into the B version it might be done now.

 

The decision to do the F-14A has not delayed the B in any way shape or form. Given their significant commonality of systems and airframe it makes sense to do both for reasons mentioned above. There just 4 significant changes made from the F-14A to the F-14A+/B (same airplane, just designation change in 1992): Engines (with associated cockpit changes), RWR, DLC, and gun venting.

 

As far as the reliability of the TF30, it was an issue but not as bad as portrayed in the OP's quote. At either zone 5 AB or full mil-power, the engine was pretty reliable. Stall margin definitely decreased at lower RPMs and throttle transients at high AOA were a bad idea. Given its less than ideal thrust, pilots generally didn't perform maneuvers much at anything less than mil and most ACM was at zone 5. There were throttle restrictions that were dependable for keeping pilots out of trouble (don't move the throttles at high AOA and don't perform high AOA maneuvers at settings besides mil-power or zone 5 AB).

 

Also, there were 2 forms of compressor stalls: "coughs" and hung stalls. Coughs are rapidly clearing stalls that don't require intervention. These did not harm the engine, but could be considered "shots across the bow". Hung stalls were the ones that placed the crew at risk of departure, spins, and engine fires. Ironically, the engine didn't fully flame out that often, but a hung stall means the engine will roll back and heat up. It refuses to respond to any command, but shutting things down and will result in critical engine temps within 30 seconds or so.

 

So if you handle the engines carelessly (like many DCS users probably would at first :) ), then there is a real risk of compressor stalls. However, watch things a bit and stalls will be pretty uncommon.

 

-Nick

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I guess so.

 

No idea which one i'll like the most.

 

Im in the same boat. They may only be different on paper. But im glad ill get to find out. If i keep getting jet washed out in the A I’ll switch to the B haha

DCS WISHLIST: F4U-4, A-4M, A-1H(AD-6), OV-10A

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Ive read that with the wings swept that it wont spin. But i dont think this information was available in 1977. obviously low speed high AOA the wings are extended though. if it starts to spin in game, manually sweeping the wings should correct this, in theory :thumbup:

 

That's one thing I'll most probably try out. My trial procedure would be:

 

- Cut throttles to idle

- Wings completely back

- Rudder to counter spin direction

- Aileron to counter spin direction as well, to get those spoilers out on that wing which still does lift (in other planes with full ailerons I'd push the stick into the spin), maybe even try to shake her out of the spin - but if that doesn't work, I'll go over to the usual way

- Stick fully forward, also maybe try shaking her down by timed up/down inputs

dcsdashie-hb-ed.jpg

 

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That's one thing I'll most probably try out. My trial procedure would be:

 

- Cut throttles to idle

- Wings completely back

- Rudder to counter spin direction

- Aileron to counter spin direction as well, to get those spoilers out on that wing which still does lift (in other planes with full ailerons I'd push the stick into the spin), maybe even try to shake her out of the spin - but if that doesn't work, I'll go over to the usual way

- Stick fully forward, also maybe try shaking her down by timed up/down inputs

 

 

Can't pretend fly as well as you can.

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I forgot to mention, the new Heatblur jet wash effect does effect TF30 stall margins: https://forums.eagle.ru/showthread.php?p=3665152#post3665152

 

-Nick

 

This was what I was hoping to have clarified. Thanks Nick.

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The decision to do the F-14A has not delayed the B in any way shape or form. Given their significant commonality of systems and airframe it makes sense to do both for reasons mentioned above. There just 4 significant changes made from the F-14A to the F-14A+/B (same airplane, just designation change in 1992): Engines (with associated cockpit changes), RWR, DLC, and gun venting.

 

As far as the reliability of the TF30, it was an issue but not as bad as portrayed in the OP's quote. At either zone 5 AB or full mil-power, the engine was pretty reliable. Stall margin definitely decreased at lower RPMs and throttle transients at high AOA were a bad idea. Given its less than ideal thrust, pilots generally didn't perform maneuvers much at anything less than mil and most ACM was at zone 5. There were throttle restrictions that were dependable for keeping pilots out of trouble (don't move the throttles at high AOA and don't perform high AOA maneuvers at settings besides mil-power or zone 5 AB).

 

Also, there were 2 forms of compressor stalls: "coughs" and hung stalls. Coughs are rapidly clearing stalls that don't require intervention. These did not harm the engine, but could be considered "shots across the bow". Hung stalls were the ones that placed the crew at risk of departure, spins, and engine fires. Ironically, the engine didn't fully flame out that often, but a hung stall means the engine will roll back and heat up. It refuses to respond to any command, but shutting things down and will result in critical engine temps within 30 seconds or so.

 

So if you handle the engines carelessly (like many DCS users probably would at first :) ), then there is a real risk of compressor stalls. However, watch things a bit and stalls will be pretty uncommon.

 

-Nick

 

 

TIL I fly the F-15 like I should be flying the F-14A

I don't think I'm ever out of full AB when I'm ACM in that jet.

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TIL I fly the F-15 like I should be flying the F-14A

I don't think I'm ever out of full AB when I'm ACM in that jet.

 

 

I'm gonna hit the brakes, he'll fly right by.....in full AB :lol:

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Jet Wash...Wake Turbulence...

 

Great! as if I needed another way to crash the plane. LoL

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