Thank you all.
My friend is part of a group who are visiting a sensitive country and it is not trivial to obtain ATC clearance to split up the formation.
I told her that flying this slow for so long on one notch of flaps to keep the nose down and maybe speed brakes (yikes) is certainly uncharted territory and even though the C400 can do it in theory, I would not just say “ok”.
I estimated that this will require as little as 25% power.
Our engines are designed for a very narrow band of RPM, MP and cylinder temps. She will probably have to lean hard to keep her CHTs alive and I don’t like the constellation. The input about vibration related damage and piston ring issues are spot on for this purpose. Thanks
If it were my plane I would say no, just too much of a misfit for the mission… A C400 is not meant for VFR sight seeing… But then she has a fantastic cross country trip to get there, so there is a reason to want to be part of it.
I offered her to do a test flight and get a feel of the aircraft and engine’s behavior before saying yes or no.
I will invite her on EuroGA Peter.
Again thanks to all
A bit of an out-of-the box-idea: fly zig-zags just behind the main formation, and to cut the routine do an ocassional 360 
aart wrote:
A bit of an out-of-the box-idea: fly zig-zags just behind the main formation, and to cut the routine do an ocassional 360
Great suggestion In addition she’ll be able to take nice pictures of all planes in formation from all possible angles.
It is more or less what you do when you are on a ski slope, and the kids and snowboarders turn up 
60 degres zigzags along the track should halve your speed or double your time (irrespective of how you do it, how many times you do it or how close you are to the track)
Wait a minute Ibra, we are a bunch of real pilots here, accustomed to calculate ETA’s to the second, so we expect some exact figures from your young sharp and mathematical brain. So, show us the exact figures, and no simplifications of the zig zag, but a true sinusoidal pattern please
The 60 degres tip comes from the “UK Royal Navigation Society”, I rarely had the time or the opportunity to fully test it but I did test the sinusoidal pattern in gliders, but you don’t need that much of it if you can share GPS locations on XCsoar screens and use a common call frequency ;)
Btw, on “real pilots”, it seems you don’t need any formation flying training to be able to fly close to another glider for 3h but you need 200h of serious training to do it in F15s for 5min, so not sure where a PPL flyout in PA28s sits in this?
aart wrote:
accustomed to calculate ETA’s to the second
On PPL skill-test juts throw a random ETA based on current time + distance to diversion airport and told the examiner you will revise it half way, the revised one should magically incorporate all source of error
aart wrote:
pilots here, accustomed to calculate ETA’s to the second, so we expect some exact figures from your young sharp and mathematical brain. So, show us the exact figures, and no simplifications of the zig zag, but a true sinusoidal pattern please
That’s real nasty, insidious demand :)
Not to be solved with flimsy tools from school mathematics.
OK so my friend just joined. Codename Majo. :-)
Ibra wrote:
Btw, on “real pilots”, it seems you don’t need any formation flying training to be able to fly close to another glider for 3h but you need 200h of serious training to do it in F15s for 5min, so not sure where a PPL flyout in PA28s sits in this?
It’s important to fly the plane you are flying I think. I guess F-15s have to be flown in a tight formation with military precision, or it will look bad That requires serious training of course. But, then again. I was almost run over by a Lancair who was catching up with me when I was flying a Cub. He knew my position, radio contact, but he just couldn’t eyeball me coming from behind with typical Lancair speed.
