Landing with a tailwind

[topcat450]

Just curious what sort of limits there are doing this - and why do it at all.

Seeing reports on the Toronto A340, they said it was landing with a 18kt tailwind component.

Presumably nose abatement, and rapidly changing wind direction can influence things? It just strikes me that a 18kt tailwind - if converted to a headwind would've reduced G/S by aprox 40mph - not an insignificant amount.

[Ropey Pilot]

One reason for doing it is that some airfields only have precision approach aids on 1 runway, the non-precision aid on the other would have a decision height above cloud base!

Another is that winds of 5 knots or so can be quite variable in direction - with the amount of traffic stacked up on approach to LHR can you imagine the chaos if everyone executed a go around and demanded a runway change every 5 mins as the "variable, less than 5 knots" wind changed direction!!!

I know some small jets have a tailwind limit of 10 kts - perhaps someone else can give some accurate figures for different types.

[The Greaser]

737 - 10kt tailwind maximum
777 - 15kt tailwind maximum

[fireflybob]

Actually I think you will find the Flight Manual limit for the B737 - 200 is 15kts tailwind.

Originally it was 10kt but I believe when Britannia were the lead customer for the B737 - 200 in the UK circa 1960s (I guess!) they applied for certification for up to 15kt. This gives more flexibility a) for "downwind" instrument approaches when lower weather minima can be applied due to type of approach aid etc and b)in the take off situation it is preferable to avoid having to fly an emergency turn (due to obstacles in the flight path) in the event of engine failure - classic example Malaga RW 32 - better to take off downwind with 15kts tailwind towards the sea on RW 14 compared to into wind on RW 32 when if an engine fails you are then doing a 180 degree turn on one engine.

I think you will find that all UK certified B737 - 200 have a tailwind limit of 15kt thanks to Britannia!

Notwithstanding the 15 kt tailwind limit this assumes that the runway is long enough to do so in accordance with the regulations.

Its also worth mentioning that tailwinds are factored by 150% when compliance with the regs are being satisfied (headwinds factored by 50 %) - this is to allow for variability of the wind although it is interesting to note that "calm" is not factored!

[The Greaser]

Most of the 737-300 and 700 I have flown have all had 10 knot limits.

[fireflybob]

Yes, The Greaser, none of the companies have been prepared to foot the bill for getting the 300 variants and beyond certified for more than 10 kt tailwind - probably not worth it so much these days with more runways served by precision approaches.

[West Coast]

US registered carriers are limited to 10 Kt tailwind landings.

[Groundloop]

LHR does not shift to easterly operations until the tailwind component exceeds 5kts. Otherwise all operations are westerly.

So at LHR landing with a SMALL tailwind component in not unusual.

[eagerbeaver]

the company i work for allows a tail wind component of up to 15kias at certain aerodromes that have been specially approved, otherwise it is 10kias.

[Preston Watson]

Duchess was around 5kts, anything more and you'd be looking at >30% increase in the LDR if I remember right.

[4Screwaircrew]

We operate a number of 737 300 with a 15 kt tailwind limit, but we have no landing data for anything in excess of 10kts :(

[ManaAdaSystem]

NG's can be bought with 10 or 15 kts tailwind limit.

It's all about the money.

[stilton]

Reading directly from my 757/767 flight manual limitations section
it states 'Take off and landing tailwind maximum 15 knots'

This is for a US registered airline.

[Khaosai]

Hi Greaser, interesting to note that our 777 FCOM states max tailwind 15kts but in the AFM it states that this finding of 15kts does not constitute operational approval to conduct take offs and landings with tailwind component in excess of 10kts. Rgds.

[Onan the Clumsy]

Uphill runway might be another reason, though probably not at Toronto.