JasonC wrote:
What is your average rate of climb/descent?The rate of descent is what I am looking for
. And at what minimum rate of descent can you maintain Vne?
My POH does not give ROD’s for given airspeeds and powersettings, so I would have to guess or try it out.
Hello Colm,
some of these points I can understand and they are logical. Clearly, local sight seeing flights will fly low as the purpose of them is to see things close up. One hour however is already quite enough to fly higher. My standard trip out of ZRH is a 1hour 20 minutes trip and generally flown at 7000 to 8000 ft. Not only is it much quieter up there in terms of turbulence, it is also faster and more economical.
Others however show in what shape PPL instruction really is. Thankfully, where I live and in the school I train and my pilots get trained, these things are done differently.As in point 3 and 4, it may well be an UK thing with airspace A all over the place. I recall discussions about the performance figures in a flight planner you well know which for the same reason had no TAS calculation as nobody in that country flew over 2000 ft. Yes, there are countries where this kind of airspace nightmare make VFR a imho unnecessarily risky way to travel.
Pilots who shy away from asking transits through CAS are lacking training imho. They are a risk and annoyance to those who need to do this regularly and know how to do it so ATC treats them as full worthy pilots, not some hillbilly who can’t utter two sentences together. Pilots who can’t interact with ATC to the point of being unable or uncomfortable asking for an airspace transit, should not have passed a PPL test.
The same goes for pilots who are unable to use modern navigation equipment. DR is a vital skill but in todays airspace maze it is one which in most cases should be supported by GPS. Airspace violations are very often comited by folks whose FI poh-pohed GPS and told them they have to fly like Lindberg when he crossed the atlantic… only then there were no airspaces and no politicians looking for excuses to limit VFR even more. Flying without modern navigation today is simply not making use of the best equipment for the purpose.
I also agree that airspaces usually become easier the higher you fly but this again may not be valid in the UK.
As for not caring for fuel consumption, maybe that is why a lot of rental planes are overpriced, because they fly with much higher consumption than necessary. I tell my pilots which cruise regime and what consumption my price is calculated for and consequently they fly it. You can fly any airplane with double the fuel flow it should be flown if you fly balls to the wall all the time and on top donˆt mix. Thankfully again I have no such Rambos on my plane.
Flying as high as possible does a lot of positive things. It reduces noise on the ground, reduces environmental impact and increases economy, as well as is usually a much more relaxed enterprise as scud running low down. Obviously it also gives you a lot more time to deal with malfunctions too and that doesnˆt only go for SEPs. Low powered twins with single engine ceilings of 5000 ft or so do a lot better in such a case if they can drift down from 10000 ft or higher first.
I honestly think that flight instruction in our areas is massively deficient if people are so limited in their abilities.
tschnell wrote:
My POH does not give ROD’s for given airspeeds and powersettings, so I would have to guess or try it out.
Without that it is impossible to calculate precisely.
JasonC wrote:
Without that it is impossible to calculate precisely.Exactly my point, see post #14
Any flight near Vne cannot be fuel efficient because of the massive amount of parasitic drag at that speed. So I cannot believe that a Vne descent makes sense in any situation – even for a glider.
Well, unless you were sitting at some high altitude with a huge tailwind and wanted to make the very best use of that tailwind for as long as possible. Then a steep descent might make sense.
It‘s great to read about all the calcalation you guys do. So I will try to simplify it drastically.
Once I read the rule of thumb, that you should use the FL which is rekated to your expected flighttime. That means 35 min flight, altitude 3500 ft. 60 minutes flight; FL 60. If I compare the figures it works out roughly well.
This is all without considering winds, which I would take in account in real live planning without doubts.
Peter wrote:
Any flight near Vne cannot be fuel efficient because of the massive amount of parasitic drag at that speed. So I cannot believe that a Vne descent makes sense in any situation – even for a glider.
I am only discussing fastest time not fuel efficiency.
But formfuel efficiency it depends upon your fuel burn at altitude. For turbines, you essentially want to stay high for as long as you can so a high speed descent is preferred.
I don’t think many piston pilots actually do any calculation at all I certainly don’t. As Dublinpilot says, most VFR flight is governed by having to stay under CAS (or under cloud) and most IFR flight is governed by the MEA (say FL090, in a few countries one can do it lower) at the bottom end and aircraft performance at the top end, and most pilots climb to stay above wx.
I posted the original article to show that the climb penalty is not as big as some might think.
MEA (say FL090, in a few countries one can do it lower)
A bit misleading though, to say the least. Discounting the fact that one can almost everywhere in Europe also cruise IFR below the airway MEAs, even if one wants to be strictly in CAS, there simply is no uniformity in this regard in Europe, since the individual airspace structures are so different:
France: generally FL70, unless high terrain is a factor
Germany: generally 3000 ft AGL
UK: whatever they chose to make the floor of the airway, anything between FL70 and FL200
Poland, Sweden: FL100
Denmark: generally FL100, but significantly lower in some places
NL: anything between a few thousand feet and FL110
Belgium: generally FL50, higher in some places
BTW, more and more countries are moving away from airways and go free-route
Peter wrote:
I don’t think many piston pilots actually do any calculation at all I certainly don’t. As Dublinpilot says, most VFR flight is governed by having to stay under CAS (or under cloud) and most IFR flight is governed by the MEA (say FL090, in a few countries one can do it lower) at the bottom end and aircraft performance at the top end, and most pilots climb to stay above wx.
As tools like GP, FF etc make doing the calculation easier, why wouldnt you consider it? They measure winds, temperatures, and match them to your performance profiles.
The easy availability of this calculation in the US through originally fltplan.com means more people use it.
And when you see the chart I posted it could save 20 minutes and over 20 gallons of fuel if you get it right.
