I flew to Cannes yesterday.
The flight turned out quite interesting.
First on weather. I knew there was a big system and a sigmet on the southwest that would make its way NE at about 20kt forecasted, and it would cover my route at some point. Icon was predicting it to hit the route at my estimated time while GFS and ECMWF not. I decided to go as I had the option to stop early and wait it overnight if needed.
I also got starlink, which was very useful to monitor in real time the system position with windy and in foreflight.
Ultimately I deviated probably 15min to the east, but manage to pass the system remaining VMC the whole time and didn’t have to stop to wait it out.
The final part of the flight turned also a bit unusual. Arriving near Cannes I was no 2 for the approach, and a few jets came in behind me and they were asked to reduce speed below 220kt or minimum clean speed (poor guys :). I had to do a 360 for spacing with the plane ahead of me.
But as I was on the RNP about the go to LUXUS, the tower told me the wind was 5kt tail wind, and could I accept straight in 35 (clearly would save everyone’s time, including mine), given long runway I accepted and did my first landing on 35 in cannes!
Interesting. I’m guessing that this was IFR. What did flyfun weather say?
roznet wrote:
monitor in real time the system positionI know that you know, but for anyone who does not – this has a lot of delay built in (about 15 minutes IIRC) and this has killed people.
roznet wrote:
the wind was 5kt tail wind, and could I accept straight in 35 (clearly would save everyone’s time, including mine), given long runway I accepted and did my first landing on 35 in cannes!Never, I’m not too fond of tailwind landings, at all – too much speed on the ground is scary.
Edit: Love the last pic…
Inkognito wrote:
Interesting. I’m guessing that this was IFR. What did flyfun weather say?
Yes, IFR. FlyFun showed ICON predicting the system reaching my route, while ECMWF and GFS didn’t. The summary was AMBER to watch for the convection at that area.
Inkognito wrote:
I know that you know, but for anyone who does not – this has a lot of delay built in (about 15 minutes IIRC) and this has killed people.
100%, and I want to be clear I am not suggesting to use this as a tactical tool. I made sure I stayed VMC all the time and could see the system and the blue sky on the other side. At some point, I had to descend 2000’ to continue remaining VMC as a layer of cloud started to reach FL170 my original cruising level. But starlink was still very useful in monitoring during the first part of the flight and knowing if I still had a chance to continue or should stop early, which I would call that more “strategic” planning. I would never fly in IMC and rely on this to avoid…
I like your analysis @roznet and how you keep comparing different sources vs reality to validate the models.
Personally I would have approached my outs differently since it seems in all cases a more or less Easterly routing would have provided an out, in my opinion better than an enroute landing, which is in any case always an option.
The plan view provides useful info that the vertical profile of flyfunweather does not. The vertical profile however provides a more clear view of which weather you will encounter at each location along your planned route, if not what alternate routing options may be best.
As to 5kts tailwind landings on a long runway I am not very worried, if you can manage the equivalent-steeper descent, since tailwind diminishes as you approach the ground, providing additional protection. A very different matter is take-off , where things are the other way around. Even on very long runways, I have been surprised by the extremely shallow climb angle and slow IAS increase after take-off with a tailwind.
Antonio wrote:
approached my outs differently since it seems in all cases a more or less Easterly routing would have provided an out, in my opinion better than an enroute landing, which is in any case always an option
In practice, routing east was my plan A and it worked. Another consideration is fuel endurance. this was a long flight for my plane, and I didn’t have option to detour for more than 45 minutes. Also planning an early stop for me is more a psychological trick for myself. I warn my wife on the other side I am 50% to stop, and I plan an airport with a hotel nearby (LFLX or LFQB if really needed big east diversion), so that if it happens and need it I don’t hesitate and don’t think twice. It helps me avoid the “let’s try a bit more” trap.
Antonio wrote:
The plan view provides useful info that the vertical profile of flyfunweather does not
Yes. and Windy is doing a fantastic job. Because Windy is so good on the 2d horizontal view, I don’t feel it’s worth investing too much on that in flyfun, I just added an easy way to jump to windy at any point in the cross section. Flyfun is really more focused on the vertical aspect of things in its display. I fully rely on windy for horizontal situational awareness.
Antonio wrote:
A very different matter is take-off
I never tried a tailwind take-off, and reading this, it occurs to me I had not considered that and especially the case of needing to go-around where it may become an issue as well… Interesting point, I need to incorporate in my thinking going forward.
I never tried a tailwind take-off,
Definitely to be avoided on a marginal runway but at LFMD you have 5000’, enough for jets to land at a touch-down speed 20-30 knots faster than us propeller types (and take off correspondingly). At LFMD I’d be fine with up to 10 knots of tailwind, though I’d certainly prefer not to.
I would worry about wheel speed with a tailwind departure.
I would worry about wheel speed with a tailwind departure.
The PoH ought to state the tailwind takeoff limitation. For my TB20, it just says:
Increase [takeoff distance] by 30 % for each 10 kt rear wind
johnh wrote:
30 % for each 10 kt rear wind
For our P210 the number is 40% for 10Kts (actually 2.5%-10kts )
I’ve done multiple 10kt tailwind landings on EGKA 02, even in the rain. The key is to be fully configured at the FAF and totally nail the speed.
