Timeline for How could I minimize the take off fuel consumption?
Current License: CC BY-SA 4.0
34 events
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| May 2 at 7:52 | history | edited | Amazon Dies In Darkness |
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| Jul 12, 2021 at 6:00 | history | tweeted | twitter.com/StackAviation/status/1414464552285188096 | ||
| Jul 5, 2021 at 2:59 | comment | added | jamesqf | @Koyovis: As long as the wheels are on the ground, the engine has to overcome rolling resistance in addition to strictly aerodynamic factors. Grass runways have higher rolling resistance than nice, smooth asphalt or concrete, particularly if the grass is long and/or wet. | |
| Jul 4, 2021 at 3:41 | comment | added | Koyovis | Voting to keep open for the second time. | |
| Jul 4, 2021 at 3:40 | comment | added | Koyovis | @jamesqf Then you might wish to explain in your answer how this would affect the condition in the question? | |
| Jul 4, 2021 at 3:01 | review | Close votes | |||
| Jul 5, 2021 at 3:54 | |||||
| Jun 29, 2021 at 6:29 | answer | added | h22 | timeline score: 0 | |
| Jun 28, 2021 at 21:09 | answer | added | Michael Richardson | timeline score: 1 | |
| Jun 28, 2021 at 17:47 | history | became hot network question | |||
| Jun 28, 2021 at 17:33 | answer | added | John K | timeline score: 2 | |
| Jun 28, 2021 at 16:55 | comment | added | jamesqf | I doubt that it's possible to provide a general answer, since it's going to depend on specific details of the aircraft. And indeed, on the runway surface. For instance, on a grass runway it might be more efficient to use some flap to get the gear out of the grass sooner. | |
| Jun 28, 2021 at 16:30 | comment | added | Kenn Sebesta | A zoom climb, what we glider pilots would call a pilot-induced thermal, is indeed a fuel- and time-optimal termination of any climb so long as we do not concern ourselves with what happens next. In fact, if the plane is not in a full hammerhead at the peak altitude, then we have not yet achieved peak optimality. To get to this second-order termination of the climb must first build on the underlying first-principles optimality. In lay speak, we have first to get within range of the zoom climb; and how to get there is, presumably, the important question being asked. | |
| Jun 28, 2021 at 16:07 | comment | added | DeltaLima♦ | @KennSebesta the zoom climb I described would not result in unsustainable flight. It would get to the termination altitude in a safe and efficient way, however any further climbing would be not optimal. The whole purpose of my clarification questions is to make sure we understand the boundary and termination conditions the OP is accepting, as there is very little context given to the question. There is nothing unfair about that. | |
| Jun 28, 2021 at 15:57 | comment | added | Kenn Sebesta | @DeltaLima I would consider a zoom climb which results in unsustainable flight as cheating and outside the bounds of the question. There are many ways to game the question: an earlier poster points out that launching off a cliff is a great way to gain relative altitude. I think it's important to be fair in our understanding of what the poster is asking. | |
| Jun 28, 2021 at 15:47 | comment | added | DeltaLima♦ | I think you may be after the most efficient climb strategy. Taking into account the fuel consumed not only during climb to cruise level, but also until a certain distance from the airport is reached. Climbing steep means that the cruise segment is longer and therefor costs more fuel in cruise segment, climbing shallow reduces the length of the cruise segment reduces the fuel burn in that segment. By comparing the total fuel consumption at a fixed distance down route where the cruise altitude has been reached makes climb strategies comparable. | |
| Jun 28, 2021 at 15:45 | comment | added | DeltaLima♦ | @KennSebesta not at all. You can climb by trading speed for height. Climbing at most economical speed to e.g. 250 ft, followed by a zoom climb to 500 ft and stall speed may get you to 500 ft with the lowest possible total fuel consumption. However, that approach will not get you to 1000 ft in the most efficient way. | |
| Jun 28, 2021 at 15:29 | comment | added | Kenn Sebesta | @DeltaLima fair question, but the word "safe" is a red herring here. The most efficient climb to any altitude is the most efficient climb to every altitude. In other words, if there is a way to climb most efficiently to 1000', then when passing through 500' it must have been most efficient there as well. | |
| Jun 28, 2021 at 15:24 | comment | added | DeltaLima♦ | What do you consider a safe altitude? | |
| Jun 28, 2021 at 15:23 | answer | added | Kenn Sebesta | timeline score: 7 | |
| Jun 28, 2021 at 15:22 | history | edited | DeltaLima♦ | CC BY-SA 4.0 |
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| Jun 28, 2021 at 14:58 | history | edited | VvV | CC BY-SA 4.0 |
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| Jun 28, 2021 at 14:01 | comment | added | quiet flyer | You need to edit the title to better match the body of the question. The title says "minimize takeoff energy" which nearly everyone will interpret as minimizing the kinetic energy of the aircraft at the instant of takeoff, but that's not what the question is actually about. Hence, the close votes-- | |
| Jun 28, 2021 at 13:31 | history | edited | Robert DiGiovanni | CC BY-SA 4.0 |
Better question
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| Jun 28, 2021 at 13:28 | comment | added | Robert DiGiovanni | A cruise climb certainly will be easier on the engine, with long term benefits there. Flaps up, provided runway length and clearances are OK, is generally more fuel efficient. | |
| Jun 28, 2021 at 11:21 | comment | added | Mike Sowsun | Yes, it is a good question. Besides flap configuration, is a shallow high speed “cruise climb” more fuel efficient than a best rate of climb? | |
| Jun 28, 2021 at 9:19 | comment | added | Koyovis | The question seems pretty clear to me, voted to keep open. | |
| Jun 28, 2021 at 8:08 | comment | added | Anonymous Physicist | The lowest takeoff energy is technically negative. This can be seen in some hang glider cliff launches. | |
| Jun 28, 2021 at 8:08 | answer | added | Frog | timeline score: 2 | |
| Jun 28, 2021 at 7:50 | review | Close votes | |||
| Jun 28, 2021 at 13:46 | |||||
| Jun 28, 2021 at 7:38 | history | edited | VvV | CC BY-SA 4.0 |
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| Jun 28, 2021 at 7:37 | comment | added | VvV | How about minimizing the total aircraft takeoff power consumption? That is use less energy to accelerate the aircraft and lift it off in air. | |
| Jun 28, 2021 at 7:36 | history | edited | VvV | CC BY-SA 4.0 |
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| Jun 28, 2021 at 7:35 | comment | added | GdD | I don't understand this question at all, what does minimizing takeoff energy mean? | |
| Jun 28, 2021 at 7:33 | history | asked | VvV | CC BY-SA 4.0 |