Simviation Forum - Density Altitude Tips...

Oct 28^th, 2011 at 5:02am

Fozzer Offline
Colonel
An elderly FS 2004 addict!
Hereford. England. EGBS.

Posts: 24861

For those times when you find that you are running out of runway length!...
...by then, its too late!... Shocked

...!

Calculating Density Altitude:

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

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!

« Last Edit: Oct 28^th, 2011 at 6:33am by Fozzer »

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Reply #1 - Oct 28^th, 2011 at 6:28am

Gregorio Offline
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Sao Paulo, Brazil

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Very cool. Not the simplest rule of thumb but also not complicated - some exercises in using it should suffice.

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Reply #2 - Oct 28^th, 2011 at 7:01am

Fozzer Offline
Colonel
An elderly FS 2004 addict!
Hereford. England. EGBS.

Posts: 24861

I am a terror for drilling extra holes in my instrument panels... Cheesy

...!

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... Wink

...!

Dell Dimension 5000 BTX Tower. Win7 Home Edition, 32 Bit. Intel Pentium 4, dual 2.8 GHz. 2.5GB RAM, nVidia GF 9500GT 1GB. SATA 500GB + 80GB. Philips 17" LCD Monitor. Micronet ADSL Modem only. Saitek Cyborg Evo Force. FS 2004 + FSX. Briggs and Stratton Petrol Lawn Mower...Motor Bikes. Gas Cooker... and lots of musical instruments!.... ...!
Yamaha MO6,MM6,DX7,DX11,DX21,DX100,MK100,EMT10,PSR400,PSS780,Roland GW-8L v2,TR505,Casio MT-205,Korg CX3v2 dual manual,+ Leslie 760,M-Audio Prokeys88,KeyRig,Cubase,Keyfax4,Guitars,Orchestral,Baroque,Renaissance,Medieval Instruments.

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Reply #3 - Oct 28^th, 2011 at 7:02am

Brett_Henderson Offline
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EVERY OUTER MARKER SHOULD
BE AN NDB

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High density altitutde.. the triple-edged sword.. 1) Less HP .. 2) Less lift .. 3) Less thrust .. Shocked

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 Sad

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.

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Reply #4 - Jan 23^rd, 2012 at 7:36am

Jokerc152 Offline
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High Speed, Low Drag!

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Maybe just me but Prop control is of the same importance as mixture control or am I worng on that :S?

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Reply #5 - Jan 23^rd, 2012 at 8:16am

Brett_Henderson Offline
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EVERY OUTER MARKER SHOULD
BE AN NDB

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Jokerc152 wrote on Jan 23^rd, 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..

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Reply #6 - Jan 23^rd, 2012 at 9:00am

Fozzer Offline
Colonel
An elderly FS 2004 addict!
Hereford. England. EGBS.

Posts: 24861

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!... Wink

...!

Dell Dimension 5000 BTX Tower. Win7 Home Edition, 32 Bit. Intel Pentium 4, dual 2.8 GHz. 2.5GB RAM, nVidia GF 9500GT 1GB. SATA 500GB + 80GB. Philips 17" LCD Monitor. Micronet ADSL Modem only. Saitek Cyborg Evo Force. FS 2004 + FSX. Briggs and Stratton Petrol Lawn Mower...Motor Bikes. Gas Cooker... and lots of musical instruments!.... ...!
Yamaha MO6,MM6,DX7,DX11,DX21,DX100,MK100,EMT10,PSR400,PSS780,Roland GW-8L v2,TR505,Casio MT-205,Korg CX3v2 dual manual,+ Leslie 760,M-Audio Prokeys88,KeyRig,Cubase,Keyfax4,Guitars,Orchestral,Baroque,Renaissance,Medieval Instruments.

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Reply #7 - Jan 23^rd, 2012 at 11:08am

Jokerc152 Offline
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High Speed, Low Drag!

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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 ??

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Reply #8 - Jan 23^rd, 2012 at 11:14am

Fozzer Offline
Colonel
An elderly FS 2004 addict!
Hereford. England. EGBS.

Posts: 24861

Jokerc152 wrote on Jan 23^rd, 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.... Cool

...!

Dell Dimension 5000 BTX Tower. Win7 Home Edition, 32 Bit. Intel Pentium 4, dual 2.8 GHz. 2.5GB RAM, nVidia GF 9500GT 1GB. SATA 500GB + 80GB. Philips 17" LCD Monitor. Micronet ADSL Modem only. Saitek Cyborg Evo Force. FS 2004 + FSX. Briggs and Stratton Petrol Lawn Mower...Motor Bikes. Gas Cooker... and lots of musical instruments!.... ...!
Yamaha MO6,MM6,DX7,DX11,DX21,DX100,MK100,EMT10,PSR400,PSS780,Roland GW-8L v2,TR505,Casio MT-205,Korg CX3v2 dual manual,+ Leslie 760,M-Audio Prokeys88,KeyRig,Cubase,Keyfax4,Guitars,Orchestral,Baroque,Renaissance,Medieval Instruments.

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Reply #9 - Jan 23^rd, 2012 at 11:55am

Jokerc152 Offline
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High Speed, Low Drag!

Gender:
Posts: 52

Aw nice one

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