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MD83FO
4th Mar 2017, 12:39
You are on a one engine missed approach, it must be flown at 1+F at an approach climb weight of 76tons and elevation of 8000 feet, S speed is 210kts but theres a turning speed limit of 185, how can we limit the speed without violating the cardinal rule of selecting speed below S ?

thanks a lot for your input.

Capt Scribble
4th Mar 2017, 12:57
You can fly the Airbus below S speed and down to VLS, our Co recommendation is a min of VLS+10.

safelife
4th Mar 2017, 13:22
If you select 1+F when going around you won't be at S speed, it's the same as a flaps 1+f takeoff.
The S speed becomes the target only after acceleration.

MD83FO
4th Mar 2017, 16:49
Ok i forgot to mention that acceleration altitude was crossed before the speed limiting turn

safelife
4th Mar 2017, 17:16
Pull speed when passing acceleration altitude, or better yet, set the acceleration altitude high enough to complete the turn first.

Hahn
4th Mar 2017, 18:19
No need to pull or set anything, it will keep SRS mode until you press "V/S 0". Just leave it alone until you passed the limiting turn and then start the acceleration.

Cough
4th Mar 2017, 19:13
Agree Hahn. Additional thought - Start a stopwatch at the start of the G/A so you don't bust the TOGA thrust time limit...

FlightDetent
5th Mar 2017, 03:45
the cardinal rule of selecting speed below S ? There is no such thing. Neither would it apply to your scenario, as you will continue to fly 1+F on Vapp anyways.

I have a question, how did you get to an OEI landing OVWG at 8k elev with 76t? Can we see the takeoff perf part of that scenario, please?

vilas
6th Mar 2017, 12:54
MD83FO
1. As FD pointed out at 8000 AAL MTOW of 76T highly unlikely.
2. OEI Acceleration altitude has no effect on flight mode.
2. when you retract to 1 you will get 1+F so it will be between 209 and 161. So close to your 185kt.
3. FCTM explains the logic below:
If a go-around CONF 1+F is carried out following an approach CONF 3, VLS CONF 1+F may be higher than VLS CONF 3 +5 kt. The recommendation in such a case is to follow SRS orders which will accelerate the aircraft up to the displayed VLS. It should be noted, however, that VLS CONF 1+F equates to 1.23 VS1G whereas the minimum go-around speed required by regulations is 1.13 VS1G.
This requirement is always satisfied.
Hope that answers the query.

Roger10-4
9th Mar 2017, 17:09
You could always just ignore the 185kts restriction if it's not with the intention of limiting your turn radius due to terrain. Also the overweight landing checklist I believe doesn't necessarily consider the fact you're single engine. The single engine go around climb gradient tables in the performance manual only include conf 2 or 3 anyway so who knows what climb gradient you will achieve single engine with conf 1+f. Happy to be corrected on that though if someone knows differently.

vilas
10th Mar 2017, 12:13
Climb gradient is always better with lower flap setting.

Roger10-4
10th Mar 2017, 16:27
I know my point was that you don't actually know what gradient you're able to achieve in this configuration as the gradients aren't published.