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Guest dynamania

Fuel mixture? <Edited>

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There was a lotta typos and mistakes in my last post i dont know whether my brain was engaged or not, sorry... anyway again..Good evening everyone,i was wondering how things really go when you are taking off a runway at an airport 9000 ft above sea level... as air density decreasesQuito (SEQU) international airport in ecuador is 9000 ft (nine thousand) above sea level, i taxi'd the A320 (cfm 26,500 lbs variant) to runway 35 which is quite a long runway and knowing that its gonna be impossible to take off normally and i tried to figure out how to enrich the fuel mixture during take off, to no avail... I advanced the throttles to TOGA and ran down the runway... first attempt just 2 seconds after take off i was in a stall and *BOOM* second time i was wiser and the plane climbed up at 1700 fpmAlthough i could climb at a higher fpm when i took off at exactly the end of the runway... Okay ive been talking to much my question is:how to produce enough thrust to take-off safely in such circumstances??dynamania

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I have just done four takeoffs from SEQU in the A319-100 which is the one I use most and which has my takeoff distance monitoring software installed.The data I had for each takeoff was as follows:Aircraft: A319-100 CFM56ZFW: 50.4 tonnesBlock Fuel: 8.0 tonnesTakeoff Weight (TOW): 58.2 tonnesConfig: 1+FThrust: TOGATrim: 0QNH: 1024Winds: tailwind 4 knotsThe takeoff distance measured was from a standing start with engines spooled up to maximum thrust before the brakes were released. The takeoff distance was measured until the aircraft was 35ft above the runway. The takeoff distances I measured were:1: 7672 ft2: 8029 ft3: 7732 ft4: 7749 ftSo they were fairly consistent, the difference being probably just a slight difference in the degree of rotation.The takeoff was therefore achieved with room to spare. I know that you used the A320 but I would not expect a significant difference. The main thing is not to be too heavy: at a high altitude airport a fully loaded aircraft, even an A319, will struggle or even fail to takeoff. I'll work on some parameters for this for you. What ZFW and block fuel were you using in the A320?Rob Elliott, EGPE InvernessPSS Airbus Support andAirbus Fleet Training Captain, British Airways Virtual airbus@speedbirdonline.co.ukhttp://www.speedbirdonline.co.uk/airbus.htmlhttp://www.bavirtual.co.uk

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Good evening,here are the parameters i used with my A320:ZFW of 134.6 (a seating conf of 150 pax, 6 flight attendants and the pilots)FOB: 11200 kg <<< wonder how things would go if i want to fly longerflap: conf 2the aircraft takeoff at the end of the runway (yes now i know why)... ive also seen a pretty IBERIAn A340-600 at SEQU on airliners.net *!!!* the A340-200/300 did better anyway, so is it only about weight?

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At a higher pressure altitude where the air is thinner engoine performance is affected and not as efficient as at a lower pressure density. One effect is that you will have to increase V1 and Vr. For SEQU at over 9000 feet this requires an increase of 6 knots in V1 and Vr which takes longer to achieve hence the longer takeoff roll. The other effect is that MTOW weight has to be reduced from the MTOW that would apply at sea level.I will have a go on the A320 with your data and see what the result is.Rob Elliott, EGPE InvernessPSS Airbus Support andAirbus Fleet Training Captain, British Airways Virtual airbus@speedbirdonline.co.ukhttp://www.speedbirdonline.co.uk/airbus.htmlhttp://www.bavirtual.co.uk

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evening, back home now and OOPS sorrythe values ive mentioned in the last post were in Pounds and not in kgsZFW: 134620 Pounds >> some 64 tonsFOB: 11,020 >>> about 5 tonsthank you :)

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