High altitude takeoffs

[coppercity]

This was from the FDUSA site, thought it was good info.

 

This past summer one of our Flight Design pilot Centers took a CTLS to Leadville CO Elevation (9927 Ft). They collected some flight data and it was compared to the AOI data.

 

Weather was:

 

Temp: 15 deg C

 

DP: 0 deg C

 

Pressure: 29.84

 

Wind: Calm

 

Density Altitude @ T/O: 12,356′

 

Aircraft weight at T/O: 1,297 lbs.

 

T/O Roll: Approximately 3,500′

 

Climb Rate after T/O: 150-200 fpm @ zero degrees flaps

 

Max altitude achieved: 12,500′

 

Max density altitude achieved, based on Dynon display: 15,050′

 

If you look at the AOI page: 150 – 200 fpm climb at approx. 12.000 ft for 1300 lbs is an excellent match; the AOI is slightly to the safe side

The takeoff roll data we publish is only to 5000′ DA.

 

If you operate out of high density altitudes be aware that the takeoff roll will be long. In this case nearly 3500 feet.

[LS Bruce]

Interesting... So what would the IAS be at the end of 3500 ft?

[FlyRatz]

Interesting... So what would the IAS be at the end of 3500 ft?

 

The same as in 0 ft?? Just my guess

 

Markus

[Ed Cesnalis]

My home field elevation is 7,100' DA's go above 11,000'. I get off the ground in about 5 seconds ~500'.

 

The recorded 3,500' take off roll sounds a bit long to me unless the flap setting was zero or less.

 

IAS at the end of the take off roll would be something above stall speed

[CT4ME]

'This is relevant information for Page Fly-in folks, as we'll be visiting Bryce Canyon Airport - elevation 7,600. DA, depending on temp, could easily go over 10,000. Fly light. Leave extra fuel and baggage in Page. Don't be surprised if you use a fair chunk of the 7,400 ft runway (especially those with props pitched for lower flying). Average Oct temps of 40-60 degrees (at KBCE) will help things a bit.

http://www.nancymoon...ryce_canyon.htm

http://www.the-adam....ce/perfect.html

http://www.swaviator...ryceCanyon.html

 

Tim

[coppercity]

Rotation IAS as well as approach IAS should remain the same regardless of density altitude since IAS is a comparison of static and ram air for the altitude you are currently at. True airspeed will increase significantly at higher DA's therefore making the longer takeoff rolls and landing rolls, plus the aircraft is not performing nearly as well so getting to speed takes longer. Where people get in trouble is trying to make the airplane climb better by pitching up more and ignoring the IAS for best climb, this leads to a very quick stall. So if you are a low flatland flyer, use you airspeed, and dont try to rely on your typical climb sight picture at sea level.

[Ed Cesnalis]

another time to rely on your IAS as opposed to sight picture is on round out - flare - touchdown.

 

to me a sea level touchdown looks like things are happening in slow motion, much like landing in a big headwind.

 

at altitude a normal landing can look more like a downwind landing due to the additional ground speed.