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Current Flight Simulator Series >> Flight School >> Density Altitude Tips...
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Message started by Fozzer on Oct 28th, 2011 at 5:02am

Title: Density Altitude Tips...
Post by Fozzer on Oct 28th, 2011 at 5:02am
For those times when you find that you are running out of runway length!...
...by then, its too late!... :o...!

Calculating Density Altitude:

http://www.flyingmag.com/technique/tip-week/calculating-density-altitude-pencil?cmpid=enews102711

Paul.... :)...!

P.S I find this procedure vital to understand, when taking off, and flying my normally-aspirated (carburettor-engined) aircraft, (Cessna 150/152, Piper Cub, Microlights, Flexwings, etc), at high altitudes!
Its where careful setting of the Mixture Control becomes essential!

Title: Re: Density Altitude Tips...
Post by Gregorio on Oct 28th, 2011 at 6:28am
Very cool. Not the simplest rule of thumb but also not complicated - some exercises in using it should suffice. :)

Title: Re: Density Altitude Tips...
Post by Fozzer on Oct 28th, 2011 at 7:01am
I am a terror for drilling extra holes in my instrument panels... :D...!

And two of the most useful gauges, I find, when flying at high altitudes in my piston-engined aircraft are:
(1) Exhaust Temp + Cylinder Head Temp gauge.
(2) Manifold Pressure gauge.

And adjusting the controls for maximum power when required!

Paul...with my trusty hole cutter, and some colour-coded wires... ;)...!

Title: Re: Density Altitude Tips...
Post by Brett_Henderson on Oct 28th, 2011 at 7:02am
High density altitutde..  the triple-edged sword..  1) Less HP .. 2) Less lift .. 3) Less thrust ..  :o



Quote:
Its where careful setting of the Mixture Control becomes essential!


Indeed.. in fact, at very high density altitude you might not even get the engine to fire, without significant leaning... and it's very easy to foul the plugs on a long taxi.. and that can skew your run-up,  'cause you're not quite sure if it's density altitude, or fouled plugs effecting RPMs  :(

If I'm taking off at high DA, as soon as the engine is running, I lean as though I'm cruising.. slowy until RPMs drop off, then slightly rich. Then at run-up (ASAP), adjust mixture for an RPM peak.. and at the begining of the takeoff roll; as important as maintaining center-line, is to adjust mixture again, for a power peak.

Title: Re: Density Altitude Tips...
Post by Jokerc152 on Jan 23rd, 2012 at 7:36am
Maybe just me but Prop control is of the same importance as mixture control or am I worng on that :S?

Title: Re: Density Altitude Tips...
Post by Brett_Henderson on Jan 23rd, 2012 at 8:16am

Jokerc152 wrote on Jan 23rd, 2012 at 7:36am:
Maybe just me but Prop control is of the same importance as mixture control or am I worng on that :S?



Yes, and no.. 

For takeoff, prop-control is a non-issue, as it its always set to highest RPM  .. and you "can" complete an entire fligt without ever adjusting prop-RPM.. the only real harm is fuel economy, and engine wear.. whereas mixture settings are critical..


EDIT:.. this is of course for light GA..

Title: Re: Density Altitude Tips...
Post by Fozzer on Jan 23rd, 2012 at 9:00am
I have fitted my little Cessna 150 Trainer out with all manner of instruments and controls, making it ideal for Flight Training, covering almost everything, including full radio navigation....>>>



My perfect little GA Trainer, keeping me up to date with all the correct techniques!

Paul... :)...!

...no expense spared!... ;)...!

Title: Re: Density Altitude Tips...
Post by Jokerc152 on Jan 23rd, 2012 at 11:08am
Brett yeah cool dont know how much of a change it makes on aircraft such as the DC-3 C-46 and the Lockheed Electra which I fly most of the time though ??

Title: Re: Density Altitude Tips...
Post by Fozzer on Jan 23rd, 2012 at 11:14am

Jokerc152 wrote on Jan 23rd, 2012 at 11:08am:
Brett yeah cool dont know how much of a change it makes on aircraft such as the DC-3 C-46 and the Lockheed Electra which I fly most of the time though ??


DC-3 Owners Manual...>>>

http://pcmuseum.tripod.com/dc3/

Paul.... 8-)...!

Title: Re: Density Altitude Tips...
Post by Jokerc152 on Jan 23rd, 2012 at 11:55am
Aw nice one :)

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