Timeline for Why couldn't my aircraft depart fully fueled on a 44C day?
Current License: CC BY-SA 3.0
13 events
| when toggle format | what | by | license | comment | |
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| Mar 7, 2017 at 21:37 | comment | added | Jan Hudec | @rbp, you are accidentally right that “more air must be ingested … by volume … fuel to be completely burnt” is wrong, because turbines work with excess air and this is not the limiting factor. However, lower density still does limit the thrust, due to RPM limit (at lower density, the same RPM gives lower mass flow) and due to temperature limit (you can add less heat to an already hot air before it becomes too hot for the turbine). So hot and high is very much a problem for turbine aircraft. The reason is just somewhat different from spark-ignited engines. | |
| Mar 7, 2017 at 20:11 | comment | added | Peter Kämpf | @rbp: Fact is, trust will be less at higher temperature. Limiting the take-off in most cases is the remaining climb speed with one engine inoperative. Above a certain temperature and aircraft mass it will be impossible to survive an engine failure above v1. Either mass or OAT must be lowered for the flight to take off safely. | |
| Jul 7, 2015 at 21:07 | vote | accept | user871199 | ||
| Jul 7, 2015 at 15:01 | comment | added | rbp | I recommend you learn about gas turbines. They are managed via "interstage turbine temperature" (ITT) not "outside air temperature" (OAT). Peace out | |
| Jul 7, 2015 at 14:58 | comment | added | rbp | 'oxygen flux' is not an english phrase, so I don't know what you mean. and writing an uniformed answer is not the place 'to learn more about this'. | |
| Jul 7, 2015 at 14:53 | comment | added | rbp | you're describing what happens in a piston engine, not a turbine. a turbine has a compressor section and a FADEC which precisely controls the air-to-fuel mixture based on the density altitude | |
| Jul 7, 2015 at 14:50 | comment | added | Calchas | @rbp In what sense is this untrue? If take off engine performance is not affected by air temperature I can delete this answer. | |
| Jul 7, 2015 at 14:47 | comment | added | rbp | @UnrecognizedFallingObject yes, but that's not what OP wrote: more air must be ingested by the engine (by volume) for the same quantity of fuel to be completely burnt. | |
| Jul 7, 2015 at 2:43 | comment | added | UnrecognizedFallingObject | @rbp -- the OAT and power demand (i.e. fuel flows needed) are both far lower at altitude than they are during a T/O. | |
| Jul 6, 2015 at 17:53 | comment | added | rbp | For jet aircraft, the first "problem" is a non-problem. if density altitude were an issue for the turbojets in modern jetliners, then they would not be able to fly at 40,000+ feet. The FADEC and the compressor of the jet engine mix the fuel in the proper proportion for the density altitude. | |
| Jul 5, 2015 at 19:40 | history | migrated | from travel.stackexchange.com (revisions) | ||
| Jul 4, 2015 at 22:16 | comment | added | Loren Pechtel | I can definitely confirm this. I live in a climate that can be very hot in the summer and we occasionally get cases of planes having to leave some passengers behind because of "weather" when it's sunny out. We don't get cancellations because there are other airports around, they can always put down for fuel if they have to. For an overwater flight, though, I could easily see a cancellation. | |
| Jul 4, 2015 at 20:25 | history | answered | Calchas | CC BY-SA 3.0 |