achimha wrote:
It is the right thing to do and it is safe and being prepared and qualified to do it is a prerequisite for VFR on top over a longer distance (read “unclear and changing weather”).
Indeed this is the right thing to do if you found yourself in that situation with no possibility of diverting or rerouting. (Although IMHO if you don’t have an IR it is an emergency and you should declare a MAYDAY.)
What would not be the right thing to do is departing on a VFR flight unless the the weather forecasts clearly show that you can expect to complete the flight – or a feasible diversion – under VFR.
I must say that my co- pilot is ifr qualified. So when it would be necessary, an ifr pick-up was our last ‘escape’.
When it was an overcast, that would be the option. With broken, we could remain VfR and descent trough the hole, but this option was more stable and safer.
Flyer59 wrote:
with falps ten the stall speed is only 50 KIAS (or so)
Do the Flaps really change the stall speed? Maybe 2 knots, at least with the hershey bar wing… Flaps IMO are mostly there to give you a better view during approach.
Peter wrote:
You would get a spiral dive if there is any turbulence.
But if there’s any turbulence then usually there are also (biggish) holes in the cloud cover? There’s even a policy at Meteoschweiz that they never report overcast if there is vertical air motion…
Thanks for a great report Vieke – a very enjoyable and informative read!
please explain how an airplane that stays precisely on a gyro heading can go into a “spiral dive”.
Actually to keep your hands off the yoke will prevent just that. As long as no wing drops the plane will not change it’s heading – and as long as you keep it precisely on a heading it will not drop a wing.
Edit:
what you probably mean is that if there is strong turbulence the rudder alone might not be effective enough to keep the wings level. That’s true i guess. But descending through a calm cloud layer the chance to lose control is higher if you use ailerons
I was also taught the “drop-down spiral descent” method (flaps 2, 45’ bank) and while if well mastered it can be very effective (you go down like an elevator), you can easily lose bearings if you don’t train it often. It is also dangerous if the cloud hole is funnel shaped as when facing the tighter bottom most people will instinctively tighten the turn to remain VMC with all the implications of it. Keeping a constant heading and descent rate to go through a layer (with nowadays instrumentation) is in my own amateur opinion easier and safer. Whether the owner of the CTR is actually going to allow you to do it is another thing. Geneva would probably tell me to bugger off if I asked.
I did that one too many times, in the Warrior: Full flaps, 45 degress bank, power idle … ;-) That produces a nice descent rate. My little daughter loves that, but then she loves the craziest rollercoasters too …
Forgive the ignorance of this VFR only pilot, but I thought the whole idea was not to have big bank angles in IMC, and that the reason that holds were not orbits was becasue continious turns tend to induce the leans ?
That spiral is only a VMC maneuversnd should only be used to descend through a big enough hole, I think.
The steep bank spiral descent is a VFR manoeuver strictly for VMC use, and the success of the manoeuver is conditioned by the cloud gap being large enough.
