The 1976 Standard Atmosphere data you have is inaccurate, infact it's almost 30 years old. And if that isn't good enough, i have data that's over 300 years old stating the world is flat.
How can the winds aloft be -200knts??? Rather to say from 0 to 200knts would be more accurate. However not a big deal, i think we all know what you mean... of course unless you've experinced a -200knt wind.
You are correct on the denisty alt, the air is thinner, creating problems for aircraft to reach that height. However a 240knt airspeed should be too diffcult to achieve, If my ground airspeed is 175knts, plus a head wind of 75knts, then my ASI would be 250knts. There is a downside to this... it only applies in a headwind.
thank you for the correction. -SkyPilot181.
p.s. To everyone -->I do not correct for spelling or grammar, if you have a problem with it... Oh well.
Keeping the UAV in cooler temps is not a problem at 65,000'.
Average temp drop 2C per 1000' or 4F per 1000'.
Median Sea Temp is 59F, at 10,000 the temp is 19F. And at 65'000 your in the Tropopause, or Stratospere. However, this can pending on the season and climate your in. Because the Troposphere can very from 20-30,000' in the winter to 50-60,000' in the summer. Either way, it's much cooler up there than the surface. So, at 65k' based on the Median Sea Temp (4F per 1k') the change in air temp would be approx 260F. Now minus 260 from 59 ='s -201F.
How can it say up there for so long?? Well if you were to look at the winds aloft at 60,000ft, you'll find it's (on average) between 75-200knts. A plane with only a 1000lbs useful load doesn't need much more than 60knts for lift. (Yes, i know the air is thinner at 65k, so a bit more speed is required to maintan lift. Perhaps 90-100knts). And based on the lifting capacity of the wings (lbs per sq ft) the ASI (Incidated AirSpeed) could be less, pending the cord angle of the wing...however i'm not the engineer this UAV.
The aircraft wouldn't require much more than 35-45% power at 65k' based on it's required lifting speeds and winds aloft. And as the aircraft burns more fuel, the lighter it becomes, requiring less power to stay in flight.
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The 1976 Standard Atmosphere data you have is inaccurate, infact it's almost 30 years old. And if that isn't good enough, i have data that's over 300 years old stating the world is flat.
How can the winds aloft be -200knts??? Rather to say from 0 to 200knts would be more accurate. However not a big deal, i think we all know what you mean... of course unless you've experinced a -200knt wind.
You are correct on the denisty alt, the air is thinner, creating problems for aircraft to reach that height. However a 240knt airspeed should be too diffcult to achieve, If my ground airspeed is 175knts, plus a head wind of 75knts, then my ASI would be 250knts. There is a downside to this... it only applies in a headwind.
thank you for the correction.
-SkyPilot181.
p.s. To everyone -->I do not correct for spelling or grammar, if you have a problem with it... Oh well.
Keeping the UAV in cooler temps is not a problem at 65,000'. Average temp drop 2C per 1000' or 4F per 1000'. Median Sea Temp is 59F, at 10,000 the temp is 19F. And at 65'000 your in the Tropopause, or Stratospere. However, this can pending on the season and climate your in. Because the Troposphere can very from 20-30,000' in the winter to 50-60,000' in the summer. Either way, it's much cooler up there than the surface. So, at 65k' based on the Median Sea Temp (4F per 1k') the change in air temp would be approx 260F. Now minus 260 from 59 ='s -201F. How can it say up there for so long?? Well if you were to look at the winds aloft at 60,000ft, you'll find it's (on average) between 75-200knts. A plane with only a 1000lbs useful load doesn't need much more than 60knts for lift. (Yes, i know the air is thinner at 65k, so a bit more speed is required to maintan lift. Perhaps 90-100knts). And based on the lifting capacity of the wings (lbs per sq ft) the ASI (Incidated AirSpeed) could be less, pending the cord angle of the wing...however i'm not the engineer this UAV. The aircraft wouldn't require much more than 35-45% power at 65k' based on it's required lifting speeds and winds aloft. And as the aircraft burns more fuel, the lighter it becomes, requiring less power to stay in flight.