570 kph in a Yak-1 at Sea Level?

[6./ZG26_Klaus_Mann]

Well, I just managed 570 kph in my Yak-1 at Sealevel using 2500rpm, full Manifold Pressure and 30% radiators. Seems a little much for an aircraft taht in soviet testing reached just 500kph which would roughly translate into best case 515-520 in western testing.

Does Winter Air really add 50 kph to the top speed? And if, why not in the 109s and 190s?

[Guest deleted@50488]

 

Does Winter Air really add 50 kph to the top speed? And if, why not in the 109s and 190s?

 

Because they're soooooo HOT!

 

And the stalls ?

 

Have you ever been in a persistent ( stupid ) turning fight, near ground, involving a 109, and/  or a Russian fighter, when you have your throttle  to the wall, you pull your stick to the stomach, the AoA is certainly well above stall AoA, but you keep turning, the nose sometimes mushing a bit but then immediately recovering... and on, and on, ...., and on....

 

Accelerated stalls are extremely difficult to get in, unless you're on an Fw190 or La-5...

Edited August 7, 2015 by jcomm

[JtD]

Does Winter Air really add 50 kph to the top speed? And if, why not in the 109s and 190s?

a) It does.

b) But it does.

[6./ZG26_Klaus_Mann]

a) It does.

b) But it does.

My 109s barely do 560. adding 50 kph to 535 kph in my 109s gets me to about 585-590.

Edited August 7, 2015 by -FDFHQ-Klaus_Mann

[JtD]

OK, so the actual question would be why you can't get your 109 to fly 585-590, not why the 109's and 190's don't gain 50 km/h due to winter conditions.

[6./ZG26_Klaus_Mann]

OK, so the actual question would be why you can't get your 109 to fly 585-590, not why the 109's and 190's don't gain 50 km/h due to winter conditions.

Well, how do you get yours to 585-590? What's your trick?

[BeastyBaiter]

But you can. The last time I checked, the 109G2 managed 578, the 109F4 590 and the Fw-190 did 580. It's also worth noting that none of them are actually going anywhere near that fast. If you check the ground speed, that 590km/h IAS on the Bf-109F4 is actually about 535km/h ground speed without any wind. It's the airspeed indicators that are off. Someone proved this definitively in one of the giant flight model threadnaughts somewhere here. I'll see if I can dig it up later.

Edited August 7, 2015 by King_Hrothgar

[JtD]

Could be that I raise the gear after take off while you don't, but it could be a million other things as well, since you never bothered to state or show how you arrived at your figures.

[6./ZG26_Klaus_Mann]

Could be that I raise the gear after take off while you don't, but it could be a million other things as well, since you never bothered to state or show how you arrived at your figures.

I very clearly stated that I do the Yak-1 at 30% rads, around 250m and just found out that the russian Instruments are Shit. 570 on the Speedo are 550 on the HUD.

Testing 109s Now with HUD. Goddamn this game is waaay too good.

I was wrong. But in some way I love this game even more now.

 

turns out I wasn't.

The G-2 with 87% Stabilizer, Auto Prop and Auto Rads does barely 554 at 200m.

F-4 is 558 at 1.3 and 580 at 1.42

Yak-1 was 551 with full power and revs, 30% rads.

Edited August 7, 2015 by -FDFHQ-Klaus_Mann

[6./ZG26_Klaus_Mann]

Fw190 according to the HUD only does 558 at 1.3 ata and 581 at 1.4

[BeastyBaiter]

Found it, near the top of the FM discussion forum. Here it is: http://forum.il2sturmovik.com/topic/16186-german-fighters-speed-testing-they-seem-pretty-darn-close/

[TWC_Ace]

the bigger problem is bug regarding flaps in Yak 1...curently you can deploy them anytime to make superuber-unrealistic turn..some folks debated about this and I was sceptical (and Im not an FM expert) until i experienced it in MP....this is the biggest FM issue...

Edited August 7, 2015 by blackram_

[Y-29.Silky]

The flaps on the Yak do remind me of War Thunder.

You get behind on their 6 and see them pull up and over, the only reaction I have is, "Hooooooooly Sh*t!". 

What's funny to see is when they don't even bother to raise them again.

[Ace_Pilto]

I don't understand this problem with the Yak's flaps, they are not incremental so don't they break off or jam if deployed at high speed? Using them over 400 kmph would have to do some damage right? And any faster than that and you're going into "Look Ma, no wings" territory.

 

Convince me that there actually is a problem here and not a bunch of butthurt 25% fuel 109F-4 drivers who got smoked in a one circle knife fight.

[YSoMadTovarisch]

Nah, the problem is that the Yak's flaps also work as anti gravity device.

[Guest deleted@50488]

I don't understand this problem with the Yak's flaps, they are not incremental so don't they break off or jam if deployed at high speed? Using them over 400 kmph would have to do some damage right? And any faster than that and you're going into "Look Ma, no wings" territory.

 

Convince me that there actually is a problem here and not a bunch of butthurt 25% fuel 109F-4 drivers who got smoked in a one circle knife fight.

 

Don't know how to convince you, but at the DED NORMAL server, I used it all of the time :-), and it Works ( as it never should... ) and it's, ridiculous, to say the least...

 

From the outside views you can easily see it working, and the flaps actually adapting their deployment to the dynamic pressure... From the cockpit, or looking at your mates or foes, you can easily glimpse the advantage they get...

 

Plain wrong, just as ( I insist... ) the inexistent accelerated stalls that all fighter aircraft, less the Fw-190, provide, allowing you to keep turning at way above stall AoA, on a low level high power carrousel, behind or ahead of your opponent...

Edited August 8, 2015 by jcomm

[Ace_Pilto]

Ahhhh, so they are magical dynamic flaps when they should just dump all the way. Riiiiiiight. 

 

I'm with you now, thanks jcomm.

[JtD]

They are not magical, and they should not deploy all the way all the time. They are being pushed in by the dynamic air pressure at high speeds, because it is larger than the static air pressure of the flaps deployment system. In general this historically correct, though some details should probably be looked into.

[Dakpilot]

Ahhhh, so they are magical dynamic flaps when they should just dump all the way. Riiiiiiight. 

 

I'm with you now, thanks jcomm.

 

They are not 'magical' they simply work in the correct historical way, it is the way that they are used/exploited (ingame) that is not historical

 

Some US navy aircraft had flaps that performed in a similar fashion

 

**EDIT** replied at the same time ^^^

 

Cheers Dakpilot

Edited August 8, 2015 by Dakpilot

[Finkeren]

I don't understand this problem with the Yak's flaps, they are not incremental so don't they break off or jam if deployed at high speed? Using them over 400 kmph would have to do some damage right? And any faster than that and you're going into "Look Ma, no wings" territory.

 

There's something fishy about the Yaks behavior flaps down, but the fact that they deploy partially at high airspeeds and open and close as speed changes is a completely correct representation of pneumatically operated flaps. It's not necesarilly good for the system, but that is how it would work.

[Ace_Pilto]

Now I'm confused. It's not a blowback valve system like on the F4F or is it?

 

Are people then spamming the flap lever or holding it down so that the flaps constantly adjust themselves? If this is so then how isn't the use of them historical? Surely you'd an advantage like this if you knew about it.

[SR-F_Winger]

I very clearly stated that I do the Yak-1 at 30% rads, around 250m and just found out that the russian Instruments are Shit. 570 on the Speedo are 550 on the HUD.

Testing 109s Now with HUD. Goddamn this game is waaay too good.

I was wrong. But in some way I love this game even more now.

 

turns out I wasn't.

The G-2 with 87% Stabilizer, Auto Prop and Auto Rads does barely 554 at 200m.

F-4 is 558 at 1.3 and 580 at 1.42

Yak-1 was 551 with full power and revs, 30% rads.

ROFL. Didnt you know that the russian craftsmanship of the time was considered flawless? All planes produced during the BOS timeframe were very much performing close to prototype values and all consistent in flawless quality. The awesomeness of russian engineering art was even able to overcome the negative effects of deployed flaps. Next thing on their agenda was to totally eliminate the laws of physics in order to totally dominate the alleged "herrenrasse". Generally the ruissian planes of the time were considered clearly superior to german airplanes. Germans had their heads too much in their own racist [Edited] to be able to create proper engineering. Just like we have it flawlessly simulated in this sim.

Cough, cough, cough, ROFL cough

/sarcasm off

Edited August 10, 2015 by Bearcat

[Sunde]

ROFL. Didnt you know that the russian craftsmanship of the time was considered flawless? All planes produced during the BOS timeframe were very much performing close to prototype values and all consistent in flawless quality. The awesomeness of russian engineering art was even able to overcome the negative effects of deployed flaps. Next thing on their agenda was to totally eliminate the laws of physics in order to totally dominate the alleged "herrenrasse". Generally the ruissian planes of the time were considered clearly superior to german airplanes. Germans had their heads too much in their own racist bu**s to be able to create proper engineering. Just like we have it flawlessly simulated in this sim.

Cough, cough, cough, ROFL cough

/sarcasm off

[Dakpilot]

ROFL. Didnt you know that the russian craftsmanship of the time was considered flawless? All planes produced during the BOS timeframe were very much performing close to prototype values and all consistent in flawless quality. The awesomeness of russian engineering art was even able to overcome the negative effects of deployed flaps. Next thing on their agenda was to totally eliminate the laws of physics in order to totally dominate the alleged "herrenrasse". Generally the ruissian planes of the time were considered clearly superior to german airplanes. Germans had their heads too much in their own racist bu**s to be able to create proper engineering. Just like we have it flawlessly simulated in this sim.

Cough, cough, cough, ROFL cough

/sarcasm off

 

Even with sarcasm (off) ....oh dear...

 

Cheers Dakpilot

[Maxyman]

Now I'm confused. It's not a blowback valve system like on the F4F or is it?

 

Are people then spamming the flap lever or holding it down so that the flaps constantly adjust themselves? If this is so then how isn't the use of them historical? Surely you'd an advantage like this if you knew about it.

 

I assume it's not 100% accurate but I'm not an expert. If the flaps are fully down they should stay like that until the lever is in the "up" position.

[Ace_Pilto]

Just looks like a pneumatic ram hooked up to a fairly standard mechanical linkage to me, I don't see any provision there for some kind of pressure sensor so it must be mounted elsewhere. 

 

So there probably should be some kind of pneumatic blow-out if the system is abused right? That would have to cause the flaps to droop as speed decreased.(Personally I think the Yak is probably too stable at low speed with flaps deployed for an aircraft with such a heavy engine compared to the 109)

[Maxyman]

Yes, that's just the cylinder that drives the flaps. Of course there's a relief valve, the air system is not shown. It also controls landing gear, brakes etc.

[Dakpilot]

I don't think there is much wrong with the way the system is modelled in the game, however in reality I imagine pilots would not risk damaging the pneumatic system in the cavalier manner that it is used ingame, The F4F Wildcat and F6 had similar system, but this was designed to be used as blow back combat flaps, and this feature is well documented as very useful in combat manoeuvres. 

 

whether the Yak flap system was also designed to be operated or used in this manner is something I have no information about

 

Cheers Dakpilot

[JtD]

You don't need to have any valves in order to have self-adjusting flaps. Air is compressible, and it is compressed inside the flaps pneumatic actuation cylinder when they are being pushed in by high speed air flow. You'd need to have a safety valve to avoid damage to this cylinder due to overpressure, which to my knowledge the Yak does not have.

[Ace_Pilto]

You don't need to have any valves in order to have self-adjusting flaps. Air is compressible, and it is compressed inside the flaps pneumatic actuation cylinder when they are being pushed in by high speed air flow. You'd need to have a safety valve to avoid damage to this cylinder due to overpressure, which to my knowledge the Yak does not have.

 

Yes but the pressure inside the actuator has to respond to the pressure generated by the speed of the aircraft somehow if the flaps are self adjustable so there must be an accumulator somewhere (with an intake) and hence there must also be a valve that regulates the pressure inside the ram at any given speed for the correct setting to be achieved. If there was nothing to regulate the actuator pressure then the flaps would always extend to the same setting because the pressure inside the ram would be constant.

 

If this wasn't the case then the system would lose pressure when it bled air while trying to extend the flaps at high speeds.

Edited August 9, 2015 by JimmyBlonde

[JtD]

If you ride a bicycle, you also need a complicated mechanism to adjust tire pressure so that the tires get properly compressed when you sit on the bike, and uncompressed when you get off? If a bicycle is too high tech, try sitting on a ball.

 

Why the fork is it so hard to understand that when flaps are being pushed in

a) the forces caused by the air flow on the flaps go down automatically

b) depending on the details of the mechanism the forces exerted by the pneumatic actuation system go up or remain constant automatically

as their angle of deployment lowers so that everything automatically settles at a new balance without any stupid valves or any sort of regulation?

[Ace_Pilto]

Bicycles wheels and balls don't have a steel housing containing the pressure in them.

[Dakpilot]

Pneumatic systems are very common in a lot of Russian aircraft, a similar system is used in the Yak 52 still manufactured under licence to this day 

 

"The Yak-52, like most Soviet military aircraft, was designed to operate in rugged environments with minimal maintenance. One of its key features, unusual in western aircraft, is its extensive pneumatic system. Engine starting, landing gear, flaps, and wheel brakes are all pneumatically actuated. Spherical storage bottles for air, replenished by an engine driven compressor, are situated behind the rear cockpit and contents displayed on the instrument panels. The operating pressure is between 10 and 50 bars (145 and 725 psi) and an emergency circuit is reserved for lowering the undercarriage if the normal supply is exhausted or the compressor fails. Additionally both main and reserve bottles can be charged from a port on the ground with compressed air, usually from a Scuba type air bottle. The ground steering/braking arrangement, especially, takes some adjustment for flyers accustomed to hydraulics, because the plane uses differential braking controlled by rudder pedals and a hand operated lever on the control stick."

 

Although a post war training aircraft its systems can be easily traced back to their origin with the Yak-1, many were sold and operated widely in the West

 

The system although similar in principle is widely different to that used on the F4/F6

 

Cheers Dakpilot

[JtD]

Bicycles wheels and balls don't have a steel housing containing the pressure in them.

Feel free to sit on an air pump, then. Just don't forget to either close the outlet or to attach any sort of pressure container there. And no valves.

[Ace_Pilto]

A 150 psi air pump? The kind that has an intake and can only pump air in one direction?

 

Flaps have to go up as well as down. This only happens if the air pressure can be changed to push the piston in the ram one way or the other I think the engineers use some kind of stupid valve for that. In fact, if you had a silly diaphragm hooked up to a ridiculous venturi system and attached this into the line you could possibly regulate the pressures inside the ram in one direction or another in direct proportion to the airspeed.

[JtD]

You could also attach a gyroscope, a cigarette lighter and a Swiss army knife. It's just as pointless. It's a self adjusting system.

 

But you're right, there is a control to raise and lower the flaps. And it uses a valve. And it has nothing to do with self adjustment.

 

Anyway, feel free to invent uncompressible air and complex control mechanisms, I don't really care.

[Crump]

A 150 psi air pump? The kind that has an intake and can only pump air in one direction?

 

 

You have correctly noted the Achilles heel of pneumatic aircraft controls. There is reason they are not commonplace but you do find them in aviation. Inevitably the seals are their weakness. Pneumatic controls are difficult to seal and end up leaking or blown.

 

Every now and then some designer will try to reinvent the wheel using pneumatic's only to end up with the same experience as every other designer before....

 

The good news is they were just a little less reliable than 1940 era hydraulics.

And you are also correct in that if you over speed the flaps you will damage the aircraft at worst and at best.....it will be down for the inspection required to check for possible damage!

[Dakpilot]

Pneumatic flaps/systems may have many drawbacks and weaknesses, however one of their advantages is well documented reliability in freezing Russian conditions, when many lend lease and German aircraft were grounded due to weather related technical issues the simpler systems carried on operating'

 

It would be good if someone who has a bit of technical knowledge on the subject could show the difference between the pneumatic flaps on the F4F wildcat and F6F Hellcat, which did not get damaged by overspeed and operated as 'automatic combat flaps' compared to those those of the Yak-1...perhaps if that info was forthcoming this issue/debate about damage could be put to bed

 

Cheers Dakpilot

[JtD]

The F6F flaps are elctro-hydraulic with an additional "blow-up" spring. The F6F flaps also have a speed switch that at about 300 km/h IAS retracts the flaps fully to avoid damage.

 

The Yak flaps are pneumatic and have nothing.

[TWC_Ace]

The question is Are Yaks flaps destructable at any speed?