Chambery Landing Wind Limits

[sad sad sad]

Having diverted twice recently as SLF on a 737-800 originally destined for Chambery (Exelair charter) I am curious whether anyone would care to enlighten me on limitations imposed by Companies and the Airport Authority v-a-v movements into/out of Chambery?

[RAGBAG]

I don't have the CMF plates to hand, but the basic problem is, as you are probably aware, Chambery is at the head of valley. An instrument approach is only available in one direction, RW18. If the wind favours the Northerly runway, 36, and the weather is good enough, then an initial approach to 18 followed by a visually flown approach to 36 can be made. However if the weather is below the minima for a visual approach then you have to land on 18. In this case you will probably find that the maximium acceptable tailwind component will be 10kts, some operators may have a limit of 15kts tail, but that would be the exception rather than the rule. An added complication could be the state of the runway. Snow or ice cover which reduces the braking action may well require a reduction in the acceptable tailwind component. If the deposits on the runway are sufficient for it to be deemed contaminated then no tailwind component would be acceptable. Just to top it all off the glidepath for runway 18 is IIRC 4.5 deg. The normal instrument approach path is 3 deg. A delightful little place! And another thing!, you can only land on RW36 by day.

Hope this goes some way to answering you question.

RAGBAG

[ 30 December 2001: Message edited by: RAGBAG ]</p>

[The Skylord]

Ragbag has most of it but the reason the 737-800 a/c diverted is the take off tail wind limit now that r/w 36 is mandatory for departures. You can do the ILS to r/w 18 but last year the DGAC ruled that the B737-800 engine out performance precludes the use of r/w 18 for departure (it used to involve a fairly precise left 90 right 270 turn after t/o and the DGAC said that the minimum terrain limits could not be met on one engine. Thus it is only possible to go into CMF if you can be sure of using r/w 36 to depart - and since the prevailing wind is southerly this has become a problem. The weight penalty is such that a fully loaded 737 cannot make it to LGW and has to tech stop in Lyons or Geneva. It is probably why Brits are not operating there this winter. The problem is made worse by the lack of an alternate where they have the handling capacity - certainly Lyons is less than satisfactory.

[In trim]

I know Chambery very well, but with the RJ100 which is less restricted than the 737 (RJ100 has 15kt max tailwind component, depending on conditions). All of what has been said above is correct and would explain the diversions.

Whilst I appreciate the apparent economics of operating a larger aircraft (737-800) into CMF, there are so many operational restrictions that it does lead to a high proportion of diversions.

A couple of other points of note in relation to CMF:

On a windy day, with the wind straight down the valley requiring landing on 36, you can operate all day with no problems. However, as soon as it becomes dark you are unable to do the visual circuit for 36, yet 18 is over tailwind limits.....most frustrating to have to start diverting at this point when the flying programme has been unaffected all day.

Decision heights are dependant on landing weight (plus other factors such as icing conditions) so in the event of low cloud you will often find that the smaller (lighter) aircraft are landing with few problems, whilst the heavier aircraft are still in the cloud at their higher decision height, so need to divert.

An interesting airport.....can be stunning to operate through, with some nice winter sun, or can be miserable as hell!