1/2 the steady-state wind?

[Minuteman]

So does anyone not do the five-knot additive to VREF? Hmm ... maybe only one particular regional that flies CRJs?

On Airbii there's the concept of GS-mini (which is similar goal, but a different idea than a wind additive). Once the destination surface winds are known, the aircraft can figure its groundspeed on short final (Managed speed minus headwind). During the approach a minimum groundspeed guarded for the case where a headwind on final reduces or turns into a tailwind. GS-mini keeps the aircraft speed more stable closer to landing.

 

[seagull]

The DC-8 I flew was 1/2 wind and all of the gust up to 20 kts, and that is the way the FCOM reads also, as I recall. That is pretty standard Douglas, and it is for any wind, not just headwind. The DC-10 and MD-11 are half the steady state wind that is over 20 kts or the full gust, which ever is more, with a minimum of 5 kt additive and a maximum of 20.

 

[BobDDuck]

Over here on the CRJ we always do ref+5 and then add in 1/2 the gust number, not to exceed 10 knots. It's pretty rare to change the speed because the +5 already covers us up to 10 knot gusts.

 

[MidlifeFlyer]

I've heard this argument before... this article explains it.

http://www.aopa.org/members/files/pilot/2010/december/proficient.html

I'm familiar with Schiff's article on the subject. I don't buy it for light aircraft. He mentions the nose-low attitude and a potential issue; to that I'd add forcing the airplane onto the ground when it's airspeed is well into the flying range.

I don't see an operational reason for it in light aircraft but thought it might be different for the big guys.

 

[shdw]

Thanks. WAG: the greater mass of these aircraft means less ability to react quickly and a need for greater stall margins. Make sense to anyone?

&engine spool up as applicable.

I agree with you completely on that article. This discussion applies to jets, for us little guys 1/2 the gust is plenty. KE increases with V squared. Accident statistics are clear -- loss of control after touchdown is a far greater issue than loss of control on final. Shame on AOPA for publishing this article for the uncertain pilot to think what an f-16 does is good practice for a 172.

 

[BobDDuck]

to think what an f-16 does is good practice for a 172.

Not to mention that an F16 has flaperons. Totally different control dynamic at slow speeds.

 

[A300Capt]

A300-600:

1/3 the steady OR all the gust which ever is greater not to exceed Vref + 15. Since we always fly Vref + 5 the most you'll ever add is another 10 kts. If a non-normal system configuration exceeds Vref 30/40 ( normal landing slat/flap setting) + 20 then we don't add any wind correction.