I don’t disagree with any of that. My only point is that Performance, in an aviation context, covers a multitude of elements. 
We crossed.
Peter, you will always get the best rate of climb at a particular IAS. However, as you climb at a constant IAS, your rate of climb will reduce because there are fewer ‘Lift Fairies’ to help:
L=Cl*1/2*Rho*V2*S
In the lift equation, the lift fairies are reflected as Rho (air density). The reduction in available power just adds to the problem; it isn’t the cause.
Dave_Phillips wrote:
L=Cl*1/2*Rho*V2*S
In the lift equation, the lift fairies are reflected as Rho (air density).
As is Velocity in the lift equation. I’ve not done a sensitivity analysis (…eugh now I’m obv going to, interest piqued) but with velocity being squared, and very much related to thrust amongst a few other variables in a steady state diagram, one might assume reduced power has at least as much effect on total lift as reduced air density.
The fact that thrust/power itself is reduced due to lower air density is another matter. :) Perhaps that is what you are alluding to in the ‘cause’
J
Doesn’t your V increase as rho decreases? (As you climb, the IAS stays constant but V (TAS) increases, presumably (at constant power) at squared root of decrease in density , no?
I have to think better about parasitic drag but the above seems correct to me
Anybody has any news on the certification process? They haven’t put up any new information on their website for quite a while.
First serially-made Panthera 540 delivered
We are proud to announce that the serial production of Panthera IO-540 flying with a Permit-to-Fly is now in full swing. A while ago we delivered the first serially-produced model and the happy owner let us take some amazing air-to-air photos of his flying beauty together with one of her older “sisters”.
https://www.panthera-aircraft.com/news
My motivation to get my IR-ticket just got a lot higher :)
Just a beautiful airframe!
Yep ! Pretty bird.
Yes this is very good news. Many people have been following this plane since the start.
My motivation to get my IR-ticket just got a lot higher :)
Will its permit have the “usual in Europe” VFR-only limitation? That is key #1. Key #2 is where you can fly IFR. In France yes, in Germany no. Etc.
But it is smart of them to shift some as Annex 2 and get them debugged, before possibly going for certification. OTOH Pipistrel may not bother at all…
I recon it would be at least 600k € and thus quite a bit to expensive without Ifr-certification or certification at all in Easa-land.
But maybe that’s just me dreaming/hoping because this is a plane (actually the only production aircraft right now) I could consider buying in the foreseeable future, but not as experimental or permit to fly (better buying a perfect turbonormalized 1980s bonanza with all bells and whistles for 300k and spend the rest on extra fuel for a long time).
It will nearly always be the case that the difference between the cost of a new plane, and some beaten up old avgas burning banger which can carry the same payload at the same speed and for the same distance, will pay for enough avgas to last you for your remaining actuarial life expectancy 
I would not pay 600k for an uncertified plane, because there are so many places one cannot fly it, and/or cannot fly it IFR.
However there is a market for uncertified (“non EASA”) planes, due to this although currently it is only in the UK, and EU politics will probably ensure that it not appear elsewhere in Europe. Presently the best touring plane which fits this requirement is arguably an RV, and the Panthera would be nicer. In fact there is a real shortage of uncertified options if you want comfort, a nice cockpit, etc. And the people who have found themselves in this hole may well pay any money to get back into flying. I know I would if it happened to me. OTOH, currently, a certified plane can be used and this may be extended post-brexit so this reason may disappear.
