air break cannot open

[SUHANG]

hi guys, did anyone encounter such problems as the mig29 cannot open the airbreak? no matter on what speed, I press B and there is no any changes. This is really troublesome when I landing. The speed is so high I just bump up on the ground. 

[razo+r]

The airbrake doesnt extend if you have the gear down or the center fuel tank on the plane (dont know which one it is). 

So plan your descent accordingly, meaning plan some room into your approach for slowing down. 

[Ironhand]

6 hours ago, SUHANG said:

hi guys, did anyone encounter such problems as the mig29 cannot open the airbreak? no matter on what speed, I press B and there is no any changes. This is really troublesome when I landing. The speed is so high I just bump up on the ground. 

As already mentioned, the air brake will not extend with the landing gear extended in green real aircraft. This is by design. If this is the only time you have an issue, that is why.

The MiG-29 is a very slick aircraft and you need to fly it accordingly. If making a straight in approach, your RPMs should be dialed back early and your speed brought down to approach speed before you start down the slope. Almost any turning approach is easier because you simply convert excess speed into Gs and don’t concern yourself with the air brake at all.

[SUHANG]

thanks for the reply. I tried again this time. It is a in flight condition, without landing gear extended. Still the air break cannot open. My speed is about 600. Is it because of the speed is too hight? What a weird design then if the airbreak extension has an speed limit ?

[Aviator78]

1 hour ago, SUHANG said:

thanks for the reply. I tried again this time. It is a in flight condition, without landing gear extended. Still the air break cannot open. My speed is about 600. Is it because of the speed is too hight? What a weird design then if the airbreak extension has an speed limit ?

You probably have a centerline drop tank then = no airbrake.

 

Drop the tank to use the airbrake, or, more realistic, try some S turns before final to bring down speed. The -29 will lose speed quickly at high alpha turns at idle thrust. Usually one hard turn into final is enough to get on speed.

Edited November 21, 2022 by Aviator78

[SUHANG]

yes, I just tried. It is the centerline tank blocked the air break. thanks

[Seaeagle]

4 hours ago, SUHANG said:

thanks for the reply. I tried again this time. It is a in flight condition, without landing gear extended. Still the air break cannot open. My speed is about 600. Is it because of the speed is too hight? What a weird design then if the airbreak extension has an speed limit ?

I cannot remember how its simulated in DCS, but the real MiG-29 does have a speed limitation for the air brake - according to the Luftwaffe flight manual its 540 KIAS. I.e at speeds above this the air brake will not deploy and if already deployed, a blow-back feature will cause it to retract under the force of the airflow(in order to protect the actuators and the panels from warping.)

As already mentioned by others, the two other limitations are:

- landing gear extended (due to danger of the lower brake panel striking the runway during landing)

- carriage of the centerline external fuel tank (cannot recall the exact reason for that).

But then 540 KIAS corresponds to ~ 1000 km/h IAS and since you said that you didn't have the gear extended and that your flight speed was "about 600", that leaves the bit concerning the centerline tank  

[draconus]

On 11/21/2022 at 12:28 PM, SUHANG said:

What a weird design then if the airbreak extension has an speed limit ?

It's very common. Higher speed can damage speedbrakes.

[Hiob]

On 11/21/2022 at 12:28 PM, SUHANG said:

thanks for the reply. I tried again this time. It is a in flight condition, without landing gear extended. Still the air break cannot open. My speed is about 600. Is it because of the speed is too hight? What a weird design then if the airbreak extension has an speed limit ?

Speed brakes (from my understanding) are not meant to slow down from Mach 1, but to prevent speed build up in a dive (CCIP bombing) or manage speed in a landing pattern.

[Mateo]

MiG-29 is very likely to reduce speed when you simply increase AOA for a moment. Real pilots sometimes even say that airbrake is absolutely not necessary at all on this aircraft.

This intense drag increase related with increase in AOA is typical on all aircraft with LEX (leading edge extension) and even more likely on delta wing aircrafts.

[BitMaster]

Wouldn't RL 29's retract the brake before actual touch down to prevent damaging the panel and other parts involved ? I would imagine so.

Maybe I find a YT vid of 29's touching down...

[draconus]

48 minutes ago, BitMaster said:

Wouldn't RL 29's retract the brake before actual touch down to prevent damaging the panel and other parts involved ? I would imagine so.

No, because they couldn't extend the speed brakes with gear down in the first place.

[Ironhand]

1 hour ago, BitMaster said:

Maybe I find a YT vid of 29's touching down…

 There are plenty of those. Just not with the air brake extended…