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high altitude takeoff

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i'm a newb to flying in fs2004 so please excuse my lack of ability.i tried to takeoff using a cessna 172 from flagstaff,ariz. and found the a/c was barely able to clear the end of the runway.i have the mixture control on auto in the a/c settings,and realize that the air is much thinner at that alt. am i using the wrong a/c for this alt. or is there something else i should be doing? i've looked for tutorials or stickies with search but found nothing. thanks

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A C172 at gross and 7000' is going to struggle. Density altitude could put the Cessna near its ceiling before it leaves the ground. You might try a lighter load or something turbocharged. Something like the default Mooney won't have any trouble climbing out of Flagstaff. Having said that, FS9 is a bit conservative on the C172 climb rate under those conditions. It's a dog at those altitudes, but not quite that bad.

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I tried this scenario, since I know that 172's are "gutless", but it worked!Pilot and passenger were the default 170 lbs * 2, and fuel load at 100%. Also summer, to add a bit to density altitude. Flaps up & rotated around 65 kias.Auto-mixture actually gave me a bit more performace than manually. With manual mixture and adjusting for best rpm , I was doing 300-350 fpm while at around 70 kias. Auto-mixture, actually let me achieve closer to 500 fpm.Didn't look at the runway from spot view, or any markers, but I must have at least had 1/4 left.Yes, as previously said, switch to the Mooney or something. I don't like the 172's takeoff/climb performance for these altitudes, although it's no problem to usually fly one at 9000-11000', depending on density altitude.L.Adamson

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Wow! I havent posted here in ages, lol.To get your Cessna to take off at such 'hot and high' altitudes, make sure that you've got 'indicated airspeed' set versus 'true airspeed'. This is found under the setting/realsim menu.Then conduct your take off using the normal V speeds. you'll notice that it'll take longer to accelerate, and you'll use more runway with reduced performance, but it'll still rotate at 70 knots.The other option you can try in addition to the above, is to deselect the auto-mixture. Then do a full power static run-up and lean the mixture for best power.This is easy to do in the default Cessna 172SP. Set the parking brakes and then open the throttle fully. Then adjust the mixture and watch the EGT gauge. Lean it out until the EGT peaks, then enrichen it by 50 degrees F. You'll want to perform this whole procedure again when airborne after you've climbed up another 2,000 FT or so. Using the above techniques, I just managed to take off rwy 21 at Flagstaff without any difficulties other than the longer take off roll and reduced performance. And yikes, Flagstaff is pretty high at 7000'MSL. No wonder you were having diffculty. A better solution for high altitude piston powered flight is something with a Turbo charger, super charger, or turbo-normalizer. All just really fancy names for engine force feeders but they will give you that added performance. Try flying the same take off with the Mooney Bravo and you'll see the difference.Hope this helps you.CF-AOA

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thanks all for the quick and concise reply...i'll take all advice and stick with the Mooney...it has proven results plus i really like its cruising speed!

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There are airports at altitude and temperatures where the math shows some aircraft will not fly.There are a lot of interesting stories of people landing at Lake County in Colorado - KLXV (highest elevation public airport in the US - 9927 ft).After they limp their Cessna into the airport to get the entry in their logbook - the airport manager will tell them to sit and relax a spell, because it will be 7-8 pm or later before the air gets cool enough to a takeoff on the 6,300 ft runway.

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Another suggestion is the Beech Baron58 TC. It's a Turbo Charged version, which maintains 0 MSL performance all the way to 20,000' ceiling without excessive pressure in the engine. Part of the secret of success in life is to eat what you like -M.Twain

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Reading this thread got me to thinkin' so I loaded up the default piper cub to 75 lb. overweight and tried Flagstaff with no wind in August. It took me four crashes to get it off the ground and climbing at 5 ft./minute at 36-37 knots doesn't exactly inspire confidence. That was after the three or four miles of "building up speed" with ground effect.Good exercise though to remind us of the huge effect of pressure altitude. Now I know why I like the Super Cub so much.I have the Lukla Mount Everest scenery and that is a real challenge even in my turbo charged Stationair.

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I'll reiterate the advice of proper mixture setting BEFORE takeoff when at higher altitudes. I did my flight training for real in Ft Collins, CO in 172's. We absolutely had to do the run up and then set the mixture as prescribed in the other post or we wouldn't get off the ground. We also put in one notch of flaps. Once set, we generally had no issues even in 80-90 degree weather with 2 people on board and about 50-75% fuel. Mike

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Yup. Last time in Denver we took my buddies C150 out of Boulder Muni. WOW! It was about 80-85 degrees F. 1 notch of flaps and tweak the heck out of the mixture at runup then held it on the runway until about 75kts and she barely cleared the lake at the west end of the runway! So, you think trying to get your 172 up at high altitude and high density altitude is miserable, try it in a 150! Actually, don't try it, I would never do that again.

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This density altitude effect can also create problems at low altitude airports.Back in the early 1970s on Guam, our A-3 Skywarrior aircraft could not make takeoffs with enough fuel (weight) to reach Japan or the Philippines on some days when the temperature was very high.That was a 10,000 ft runway at 298 ft ASL but when the temp got into the mid-90's - there was not enough runway for them.

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