Sorry Henning, I should have posted make and model. I did not think that important I was just giving an example that I hoped would help some. That set of numbers is for a Cheyenne IIIA. Ain't no 200 going to do that. Settle down I am just kidding, sort of!
Yes, once you temp out, speed is SOMEWHAT constant. Once you are temped out power will go down as you go up. However the thinner air ALMOST compensates for it. In short, very general terms, altiude is used to get fuel flows down without giving up much speed.
I should have given you true airspeed for each altitude. Those times take into consideration the forcast winds and temperature at each altitude. The plane is faster at FL190 than at 280 by at least 10 knots. You had no way of knowing that from what I posted.
To give you an idea of TAS let us assume a standard day (quite cool, makes the IIIA look better ) 700 pounds below gross at take off.
TAS at FL180 will be about 295K., useing about 720 punds/hr. Ouch!
At FL280 about 287K.,useing less than 600 pounds/hr. So I give up 8 knots to save at least 120 pounds of fuel. That is a pretty good trade.
Now the plane itself: 11,200 pounds MTOW. Useful load just over 4000 pounds. In the example a VFR trip could have been made with at least 1700 pounds of people with a tad over 800 pounds in reserve.
I hope I did a little better in this follow up giving you info you were looking for.
EDIT: I forgot you asked for max range. It will hold a little over 3700 pounds of fuel which means about 5 hours with a 1 hour reserve, again depending on altitude.
Yes, once you temp out, speed is SOMEWHAT constant. Once you are temped out power will go down as you go up. However the thinner air ALMOST compensates for it. In short, very general terms, altiude is used to get fuel flows down without giving up much speed.
I should have given you true airspeed for each altitude. Those times take into consideration the forcast winds and temperature at each altitude. The plane is faster at FL190 than at 280 by at least 10 knots. You had no way of knowing that from what I posted.
To give you an idea of TAS let us assume a standard day (quite cool, makes the IIIA look better ) 700 pounds below gross at take off.
TAS at FL180 will be about 295K., useing about 720 punds/hr. Ouch!
At FL280 about 287K.,useing less than 600 pounds/hr. So I give up 8 knots to save at least 120 pounds of fuel. That is a pretty good trade.
Now the plane itself: 11,200 pounds MTOW. Useful load just over 4000 pounds. In the example a VFR trip could have been made with at least 1700 pounds of people with a tad over 800 pounds in reserve.
I hope I did a little better in this follow up giving you info you were looking for.
EDIT: I forgot you asked for max range. It will hold a little over 3700 pounds of fuel which means about 5 hours with a 1 hour reserve, again depending on altitude.
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