Why no Flap blow up at speed

[ricktoberfest]

So after flying the F4 I’m wondering why the F14 (which is newer) doesn’t have the flaps blow up above flap speed like the F4 does?  I’m pretty sure that it’s true to life as heatblur does tons of research, but why didn’t they implement this safety feature IRL?  The only reason I can think of is maybe something to do with the variable sweep wing but that’s just a guess. 

[aaronwhite]

1 hour ago, ricktoberfest said:

So after flying the F4 I’m wondering why the F14 (which is newer) doesn’t have the flaps blow up above flap speed like the F4 does?  I’m pretty sure that it’s true to life as heatblur does tons of research, but why didn’t they implement this safety feature IRL?  The only reason I can think of is maybe something to do with the variable sweep wing but that’s just a guess. 

Good question. I wonder if the F-14's wings were just already complex enough? Or maybe with the wing sweep being handled by the system, the wing would normally be in an auto mode that would pull the flaps in to sweep the wing anyhow? I'm curious to see what people say. 

[WarthogOsl]

Something to do with the torque rod arrangement the F-14 had for flap actuation, I'd assume.  Perhaps due to the variable sweep wing, as you say.

One thing that apparently does blow up is the tail hook, above 400 or 500 knots or so.  The transit light remains lit in that case.  It wouldn't really effect anything, but it would be a nice detail to see in the future.

[Gareth Barry]

I guess Grumman expected that pilots would fly according to the manual, and not lower the flaps above 220 knots? ^-\/(",)\/^-

On a serious note, I have found myself, on more than one occasion, being a bit late in raising the flaps after a cat-shot, see the plane start to shudder and shake, look at the airspeed indicator, see that I'm doing 300 knots, with the flap lever still down, and think 'thank goodness I was never a Navy pilot....' I wonder if that ever happened in real life? I am thinking maybe it is just down to complexity, but having said that, I wonder why logic wasn't programmed in that the flaps would be raised if above a certain airspeed regardless of handle position, and could not be fully lowered if above a certain airspeed? I mean, the f14 did have the first real microprocessor as I understand it, in the form of the CADC?

I wish we could interview more Grumman engineers from this time period. 

[Rhrich]

Overspeed. Did it ever happen. Sure. 
Some planes are more susceptible than others. I've talked to Lightning pilots, they had to be real quick with the gear.

In the F-14 you get a "slow down" warning, but nothing will override the pilot.
It's been a shift in mentality. In my day any system that overrided the pilot was treated with suspicion and I frankly spent far too long opposing them.
Nowadays some folks tend to think that the computer or some safety system should override the pilot if some boffin in a office thinks the pilots doing something wrong.

In my mind, both extremes are wrong and when I see things like AF447 I tend to think things have gone too far. But I'm a dinosaur.

 

To the spesific question: I'm sure there was good reasons. And agree a boffin-interview would be interesting.

 

[captain_dalan]

3 hours ago, Gareth Barry said:

I mean, the f14 did have the first real microprocessor as I understand it, in the form of the CADC?

 

There's several good videos on YouTube on the topic of these early microprocessors. Suffice to say, while they were lightyears ahead of everything that came before, in terms of what modern people think when CPU's are mentioned, and the technology available from the 80s onwards....... let's just say, that thing had to work its semiconductor butt off, just to process the data needed for the wing sweep.

Edited May 30, 2024 by captain_dalan

[JetCat]

The Tomcat has flap damage modeled. Every third launch I get this by accident because the afterburner is accelerating this beast to 300 or 400 knots in seconds, this overspeed for extended flaps leads to one flap getting stuck and not retracting anymore. The wing sweep gets stuck too because of the damaged flap.

And the flaps-damaged Tomcat can only fly straight ahead with full aileron trim + rudder trim in the opposite direction of the hanging out flap, otherwise it wants to roll and needs constant counter-steering.

But the flaps are not getting ripped off the wing, only stuck. Has the Phantom an animation with flaps getting ripped off? A good and realistic damage model makes an airplane very loved and wanted, and I still have to decide to buy the Hind or the Phantom next

[aaronwhite]

8 hours ago, Gareth Barry said:

I guess Grumman expected that pilots would fly according to the manual, and not lower the flaps above 220 knots? ^-\/(",)\/^-

On a serious note, I have found myself, on more than one occasion, being a bit late in raising the flaps after a cat-shot, see the plane start to shudder and shake, look at the airspeed indicator, see that I'm doing 300 knots, with the flap lever still down, and think 'thank goodness I was never a Navy pilot....' I wonder if that ever happened in real life? I am thinking maybe it is just down to complexity, but having said that, I wonder why logic wasn't programmed in that the flaps would be raised if above a certain airspeed regardless of handle position, and could not be fully lowered if above a certain airspeed? I mean, the f14 did have the first real microprocessor as I understand it, in the form of the CADC?

I wish we could interview more Grumman engineers from this time period. 

Reminds me of the Hornet when I was learning it. I wouldn't get the gear up quick enough when I was doing full afterburner takeoffs and would constantly rip the gear doors off on the nose. 

[Victory205]

Believe it or not, the F14 did have a provision for the flaps and slats to automatically retract.  If the flap handle was in the normal range (ie, not in emergency), then an overspeed that exceeded 225 KIAS would auto retract the main flap panels. However, this feature was removed in an airframe change (AYC 660P1). I am not sure of the actual timeframe of the change, but I never flew an aircraft that had the auto retract capability. 

Auto retract was originally confined to certain BuNo's, but was removed in all aircraft by the airframe change. I'm not 100% sure why it was removed, but if memory serves, it was likely due to inadvertent retractions occurring below the 225 KIAS trigger speed.

Exceeding 225 KIAS with the landing flaps extended is one of the three states that activates the "Reduce Speed" warning light, so all F14 aircraft will show that warning.

All F14's also have an AUX FLAPS blow back feature due to a bypass valve located within the aux flap control section of the combine hydraulic system. So technically, the F14 does have a blow back feature, but only for the AUX FLAPS. 

[Askeladd]

En 30/5/2024 a las 12:14, Victory205 dijo:

Believe it or not, the F14 did have a provision for the flaps and slats to automatically retract.  If the flap handle was in the normal range (ie, not in emergency), then an overspeed that exceeded 225 KIAS would auto retract the main flap panels. However, this feature was removed in an airframe change (AYC 660P1). I am not sure of the actual timeframe of the change, but I never flew an aircraft that had the auto retract capability. 

Auto retract was originally confined to certain BuNo's, but was removed in all aircraft by the airframe change. I'm not 100% sure why it was removed, but if memory serves, it was likely due to inadvertent retractions occurring below the 225 KIAS trigger speed.

Exceeding 225 KIAS with the landing flaps extended is one of the three states that activates the "Reduce Speed" warning light, so all F14 aircraft will show that warning.

All F14's also have an AUX FLAPS blow back feature due to a bypass valve located within the aux flap control section of the combine hydraulic system. So technically, the F14 does have a blow back feature, but only for the AUX FLAPS. 

And in the latest update the auxliary flaps gets stucked and doesn't blowback. Instead the maneuvering flaps gets damaged and blown back... Shouldn't that the other way around?? And I think there is no documentation of the maneuvering flaps when they overspeed they get damaged and the get blown back. Even Dale Snodgrass deployed the full flaps at 325 knots, and didn't report any blow back or ctitical damage.

Edited July 13, 2024 by Askeladd