Airbus bank vs Maneuvering speeds
 

By definition maneuvering speeds protect from stick shaker in current configuration in 15° banks adding a 25° overbank protection.

1-Is there then a reason why FCOM defines Vapp as a maneuvering speed? For sure it's lower than Vstall (or stick shaker) at 40° bank (15+25).

2-Why in HDG lateral mode FD commands 25° bank below maneuvering speeds? I suppose that in a manual flight with no FD an instructor wouldn't be happy to see a guy banking 25° below maneuvering speeds...

all comments appreciated..

Might be completely misinformed here but my understanding is that at and above maneuvering speeds you can manoeuvre up to the limit of +2.5g (+2g in Conf 1 and above). Below these speeds you get whatever the aeroplane is capable of giving and will see bank angle reduce accordingly.

My questions was different..

Which Airbus are you talking here? No stick shaker on 320/330.

There are no stick shakers on any Airbus aircraft these days.

From the 320 Series FCOM

The AP /FD Limits bank angle as follows:

• 15 ° when the aircraft speed is below the maneuvering speeds (F, S, or Green
Dot speed) -10 kt

• Then linear increase to 25 ° up to maneuvering speeds (F, S, or Green Dot
speed) -3 kt

• 25 ° above maneuvering speeds (F, S, or Green Dot speed) -3 kt.

For Engine Out it's the same.

I'm not sure I understand your question. Basically VAPP is manuveur speed in CONF 3 or CONF FULL - why would you want to bank > 25° at this stage? Even on a circling approach (FD's off) you shouldn't bank more than 25°...... and VAPP is going to be VLS+5 so, theoretically, at VLS+2 (maneurver-3) you can still get a commanded angle of 25°.

A4

My airbus had a stickshaker:).

But it computed maneuvering speeds the wrong way, e.g. increasing bank - speeds lowered and v.v., a well known bug, nobody cared for....

A4

except in OEI situation HDG lateral mode will lead to bank 25° whatever the speed, try it

Where do the 40° bank angle come from?

The max is 30°, but you cant see that... The FMS will command to 25° and leave 5° internally for course change while in the turn....

40 is 25 plus an allowable over bank of 15 degrees which equals your 1.3g manoeuvre limit.


How do you get the 'degree' symbol?!

Just Copy & Paste from the previous post. The actual HTML code is ° but this forum will not accept it.

I know this is completely off topic, but ALT+167 works just fine ---> º

Can't speak to Apple, but on the MS variants, one conveniently finds all the non-keyboard symbols in the character map applet. On my installation that is located at

Windows\System32\charmap.exe

So nobody has explanation on the hdg mode vs below maneuvering speeds logic?

At FL370 at 0.78 if you are in managed NAV you will get 15* in a 90 deg turn. Pull HDG and you get 25*

sorry compressor stall,

that's not the point of the topic...