B737 Break-away thrust?
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From: USA
Thread Starter
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From: RAINBOW
Thanks for all your answers guys. But here I'd like to say that despite many ideas; still missing the correct amount. Some ppl says it depends on weight, temperature etc. Of course, but it's meaningless to say that as we are all airliners. I do not want to extend the question but you should get it that what I was gonna ask was for normal Standard conditions.
So the some ppl says 35%N1 is normal limit but any source for that amount of thrust?
And here comes the second question; what should be the minimum distance to get closer to another aircraft? Same problem we had; what I ve been told is that it should be 50 m. minimum. (could depend on the types but I ask for same types) And when I ask the source, he told me that's an Air Law rule but I checked for that on Jeppesen Air Law book, not found.
Any idea?
So the some ppl says 35%N1 is normal limit but any source for that amount of thrust?
And here comes the second question; what should be the minimum distance to get closer to another aircraft? Same problem we had; what I ve been told is that it should be 50 m. minimum. (could depend on the types but I ask for same types) And when I ask the source, he told me that's an Air Law rule but I checked for that on Jeppesen Air Law book, not found.
Any idea?
Joined: Apr 2010
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From: IRS NAV ONLY
normal Standard conditions
Idle thrust is adequate for taxiing under most conditions. A slightly higher thrust setting is required to begin taxiing.
An instructor I've flown with uses half of the take off as a guideline maximum limit without obtaining a clearence from the tower.
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From: On SBY next to my phone
N1 of course, more convenient than calculating kilo newtons when taxying on the apron 
I've yet to find where it's written if there is such a thing at all, apparently a small piston aircraft was damaged due to the jet blast a while ago and the company were hold nonresponsible since they could prove that less than half of the take off thrust N1 was used, according to him. While the subject is up for discussion, I would like to ask if anyone has heard anything similiar?
I've yet to find where it's written if there is such a thing at all, apparently a small piston aircraft was damaged due to the jet blast a while ago and the company were hold nonresponsible since they could prove that less than half of the take off thrust N1 was used, according to him. While the subject is up for discussion, I would like to ask if anyone has heard anything similiar?
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From: last time I looked I was still here.
And here comes the second question; what should be the minimum distance to get closer to another aircraft? Same problem we had; what I ve been told is that it should be 50 m. minimum
And much depends on what you are and what they are. A PA-31 behind a B747 is >50m. You'd get airborne if they went 40% break away. I was very nervous when I was in front of a B747 and I felt his shadow cover me like a shark over a scuba diver. I doubt he could even see me, so I reminded him I was first and still there. I once heard (rumour) of some guys in a DC-9 type a/c, who were getting close to their hold-over time during a lengthy taxi in USA, and it started to snow again, that "maybe we should get it close to the B747 jet blast and clean the wings a bit?" An A319 or EMB135 behind an A380 might be shaken not stirred if too close.
It's not an exact science, more common sense.
And much depends on what you are and what they are. A PA-31 behind a B747 is >50m. You'd get airborne if they went 40% break away. I was very nervous when I was in front of a B747 and I felt his shadow cover me like a shark over a scuba diver. I doubt he could even see me, so I reminded him I was first and still there. I once heard (rumour) of some guys in a DC-9 type a/c, who were getting close to their hold-over time during a lengthy taxi in USA, and it started to snow again, that "maybe we should get it close to the B747 jet blast and clean the wings a bit?" An A319 or EMB135 behind an A380 might be shaken not stirred if too close.
It's not an exact science, more common sense.
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From: FL410
So 737 behind 737 need to be able to fit 737 between tail and nose, 737 behind 777 need be able to fit 777 between tail and nose... except Germany where 737 behind 777 requires 200m.
This distance (preceding aircraft length) prevents the trailing aircraft being damaged by engine jet blast from the preceding aircraft, which generally speaking would have more jet blast the bigger the aircraft...
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From: FL410
Used to be contained in Jeppesen supplement, ATC section - Germany variations.
Will need to look up where they got their reference from
Will need to look up where they got their reference from
Jeppesen Airway Manual
STATE RULES AND PROCEDURES - EUROPE
GERMANY
RULES AND PROCEDURES
AVOIDANCE OF WAKE TURBULENCE
f) When taxiing behind an aircraft of higher wake turbulence category a minimum distance of 200m should be kept whenever possible.
STATE RULES AND PROCEDURES - EUROPE
GERMANY
RULES AND PROCEDURES
AVOIDANCE OF WAKE TURBULENCE
f) When taxiing behind an aircraft of higher wake turbulence category a minimum distance of 200m should be kept whenever possible.
Last edited by Skyjob; 25th April 2015 at 15:58. Reason: Included quote from manual
Prof. Airport Engineer
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From: Australia (mostly)
B737 Break-away thrust?
ACMS - I knew the DXB problem you refer to, and the asphalt rutting was fixed shortly afterwards. I also know the BKK/VTBS rutting problems but don't anticipate any early resolution.
