Pilot Creates Delay To Avoid Wake Turbulence
Jun 12, 2021 | 4:53 am
#1
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Pilot Creates Delay To Avoid Wake Turbulence
What would happen if, with planes lined up to take off, one pilot determines that air traffic control did not allow enough time for the previous departure wake turbulence to dissipate and he intentionally dilly dallies on his own takeoff, perhaps filling the 15 or so seconds with a little banter on the subject with ATC.
Jun 12, 2021 | 9:06 am
#2
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I'd give the pilot a prize. He acts from experience. Having once experienced severe wake turbulence upon landing (where the plane was tilting sharply from side to side, wingtips pointed toward the runway over the SFO runway) where the pilot had to promptly get us back to altitude, I will not question the pilot's action.
Jun 12, 2021 | 10:51 am
#3
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safety first … the captain has the final say
safety first … the captain has the final say
Jun 12, 2021 | 11:25 am
#4
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The FAA's Aeronautical Information Manual (AIM) offers the following guidance.
Pilots may request additional separation (i.e., 2 minutes instead of 4 or 5 miles) for wake turbulence avoidance. This request should be made as soon as practical on ground control and at least before taxiing onto the runway.
NOTE-
14 CFR Section 91.3(a) states: “The pilot-in-command of an aircraft is directly responsible for and is the final authority as to the operation of that aircraft.”
Pilots may request additional separation (i.e., 2 minutes instead of 4 or 5 miles) for wake turbulence avoidance. This request should be made as soon as practical on ground control and at least before taxiing onto the runway.
NOTE-
14 CFR Section 91.3(a) states: “The pilot-in-command of an aircraft is directly responsible for and is the final authority as to the operation of that aircraft.”
Jun 12, 2021 | 10:38 pm
#5
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What would happen if, with planes lined up to take off, one pilot determines that air traffic control did not allow enough time for the previous departure wake turbulence to dissipate and he intentionally dilly dallies on his own takeoff, perhaps filling the 15 or so seconds with a little banter on the subject with ATC.
As the AIM states in the above post, the extra delay should be taken prior to entering the runway.
Jun 13, 2021 | 9:50 pm
#6
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While that is all well and good in theory, the delaying pilot may not be 100 percent aware of what particular aircraft is involved at that time.
Jun 14, 2021 | 11:09 am
#7
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Thanks.
Oh, by the way, the pilot in question will not be aware of much. All he knows is that the previous plane took off and, after a short pause, ATC gave him the go ahead. In this hypothetical scenario the pilot judges that by the time he would get into position on the runway and should take off himself, the previous plane would not be far enough away. So, still at the front of the takeoff queue, the pilot places his request to ATC for more time.
Oh, by the way, the pilot in question will not be aware of much. All he knows is that the previous plane took off and, after a short pause, ATC gave him the go ahead. In this hypothetical scenario the pilot judges that by the time he would get into position on the runway and should take off himself, the previous plane would not be far enough away. So, still at the front of the takeoff queue, the pilot places his request to ATC for more time.
Jun 14, 2021 | 10:03 pm
#8
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Thanks.
Oh, by the way, the pilot in question will not be aware of much. All he knows is that the previous plane took off and, after a short pause, ATC gave him the go ahead. In this hypothetical scenario the pilot judges that by the time he would get into position on the runway and should take off himself, the previous plane would not be far enough away. So, still at the front of the takeoff queue, the pilot places his request to ATC for more time.
Oh, by the way, the pilot in question will not be aware of much. All he knows is that the previous plane took off and, after a short pause, ATC gave him the go ahead. In this hypothetical scenario the pilot judges that by the time he would get into position on the runway and should take off himself, the previous plane would not be far enough away. So, still at the front of the takeoff queue, the pilot places his request to ATC for more time.
Jun 14, 2021 | 10:30 pm
#9
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Oh, by the way, the pilot in question will not be aware of much. All he knows is that the previous plane took off and, after a short pause, ATC gave him the go ahead. In this hypothetical scenario the pilot judges that by the time he would get into position on the runway and should take off himself, the previous plane would not be far enough away. So, still at the front of the takeoff queue, the pilot places his request to ATC for more time.
As always, the pilot in command is the final authority to operate the aircraft, but could be required to leave the runway for other traffic.
Jun 15, 2021 | 9:43 am
#10
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What would happen if, with planes lined up to take off, one pilot determines that air traffic control did not allow enough time for the previous departure wake turbulence to dissipate and he intentionally dilly dallies on his own takeoff, perhaps filling the 15 or so seconds with a little banter on the subject with ATC.
Last edited by freshairborne; Jun 15, 2021 at 9:49 am
Jun 15, 2021 | 9:48 am
#11
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When wake turbulence is involved, takeoff clearances are predicated on weight class of preceding aircraft (small/large/heavy/super) and the succeeding aircraft. It can be measured in whole minutes 2/3/4 or radar distance, but would not be a short pause. The takeoff clearance cannot be issued until the prescribed interval in time or distance has passed.
As always, the pilot in command is the final authority to operate the aircraft, but could be required to leave the runway for other traffic.
As always, the pilot in command is the final authority to operate the aircraft, but could be required to leave the runway for other traffic.
Jun 15, 2021 | 11:59 am
#12
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ATC usually gives us enough spacing, and that becomes the expectation. In some situations they don't, and we won't necessarily know that ahead of time. A lot depends on the conditions and our weight, which affects our ability to stay above the preceding aircraft's wake.
Jun 15, 2021 | 3:31 pm
#14
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Another problem is the 757s excellent climb performance. It was able to climb more steeply than most of the aircraft hat might be following it which put those aircraft into its wake more often than would normally occur.
Jun 20, 2021 | 12:18 pm
#15
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Once ATC gives the, "go ahead" obviously that means the pilot CAN go. Does anyone know how long he/she has to pause before they MUST go? Is it essentially expected that they immediately go once given clearance? Presumably, ATC is timing things and is expecting the pilot to be out of the way shortly.
I suppose it could be different if the same runway is being used for take-offs and landings whereas one used just for take-offs wouldn't be as critical.
I suppose it could be different if the same runway is being used for take-offs and landings whereas one used just for take-offs wouldn't be as critical.