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Use of Reverser on the 737 classics and -900

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Old 5th Jan 2009, 12:14
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Use of Reverser on the 737 classics and -900

Hi guys, just would like to know your "daily" usage of thrust reversers during normal operation on 737 classics and -900, Is it the second detent, or full reverse is often used?

Cheers.

SS
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Old 5th Jan 2009, 12:46
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The 'norm' is to follow company guidelines which vary from company to company and also from landing to landing. I assume that now-a-days, if there is a 'norm', it would be reverse idle. What are your company's SOPs on the 310?

Last edited by BOAC; 5th Jan 2009 at 14:06.
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Old 5th Jan 2009, 19:25
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Silver Spur, I fly the -900's for the outfit just up the road from you and our company policy is that reverse must always be selected. My personal opinion is that the -900's performance is poor, and at the moment company policy is to tanker fuel, so nearly always landing heavy away from base. End result is that I nearly always end up using 2nd detent reverse.

Last edited by Capt Chambo; 6th Jan 2009 at 22:51. Reason: Replace "full" with "2nd detent"
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Old 5th Jan 2009, 22:51
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Full reverse, every time is the SOP at my outfit. Auotbrake as required.
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Old 6th Jan 2009, 12:25
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Hey SS,
I've flight tested the 900's and 800's in VARIOUS configurations on numerous occassions,besides training on both.And of course company SOP's notwithstanding,i've found that a gentle mix between unlock detent and second detent modulated back to idle by about 60kts,works well for me more than 90% of the times.Thats also what I teach online and in sims.
Having said that,if u landing on a 2.5 mile strip,no need for more than idle/Mlw on a 1 mile strip,i'd use max reverser!
My 2(or less)cents worth.....
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Old 6th Jan 2009, 17:56
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Some comments on this thread indicate a lack of understanding of reverser use on the 737 models.
Full reverse, every time is the SOP at my outfit
Really? That goes against Boeing guidance from the FCTM (repeated below for info).

"After touchdown, with the thrust levers at idle, rapidly raise the reverse thrust
levers up and aft to the interlock position, then to the number 2 reverse thrust
detent. Conditions permitting, limit reverse thrust to the number 2 detent."

Many pilots I fly with are not completely familiar with the various detent positions. Again, look at the diagram in the FCTM which explains all.

My personal opinion is that the -900's performance is poor, and at the moment company policy is to tanker fuel, so nearly always landing heavy away from base. End result is that I nearly always end up using full reverse.
Unless you are doing this to keep the brakes cool, then again, some misunderstanding of what reverse thrust does is being displayed. Unless you are landing on a slippery runway, use of more than idle reverse thrust will not stop you quicker (i.e. improve your landing performance), it will merely modulate the brakes to achieve the same deceleration rate as if you used idle reverse (detent 1).

i've found that a gentle mix between unlock detent and second detent modulated back to idle by about 60kts,works well for me. Thats also what I teach online and in sims.
Again, not how Boeing say it should be used;

"Maintain reverse thrust as required, up to maximum, until the airspeed approaches 60 knots. At this point start reducing the reverse thrust so that the reverse thrust levers are moving down at a rate commensurate with the deceleration rate of the airplane. The thrust levers should be positioned to reverse idle by taxi speed, then to full down after the engines have decelerated to idle."

Note that they should remain at the selected setting until 60kts decelerating, not 'modulated back to idle by 60kts', which is a common mistake seen on the line, as is stowing them at 60kts when only reverse idle has been selected.

The only time Boeing recommend maximum reverse thrust, i.e. beyond detent 2, is with non-normal landings, such as an overweight landing, flapless landing or flat main gear tyre etc.

PP.


p.s. Edited to add, 'norm' in my company is idle detent unless more is needed. You will find that many airfield briefs stipulate limiting thrust to reverse idle unless for safety reasons.....due to noise.

Last edited by Pilot Pete; 6th Jan 2009 at 19:00.
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Old 6th Jan 2009, 22:49
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Full reverse, every time is the SOP at my outfit Really? That goes against Boeing guidance from the FCTM (repeated below for info).
Pilot Pete you are quite right and I stand corrected. Our company SOP is not for Max reverse which is the impression I gave by saying "full reverse".
It is for detent two. And even then there are exceptions such as when cleared to roll through to the end of the runway etc.
Regards, Framer.
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Old 7th Jan 2009, 06:48
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Unless you are landing on a slippery runway, use of more than idle reverse thrust will not stop you quicker (i.e. improve your landing performance), it will merely modulate the brakes to achieve the same deceleration rate as if you used idle reverse (detent 1).
That of course is only true if you rely solely on autobrakes for deceleration. I know some outfits do that, others still require minimal use of autobrake and only use it on wet, contaminated, reduced braking action and limiting airfields or situations.
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Old 14th Jan 2009, 12:21
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Hi All,

Many thanks for the various input for the -900, been helpful indeed.

For BOAC, my company SOP for the 310/300-600 is to select 1st detent upon touch down as to get the REV GREEN, the go full reverse after the NW touch down. Start braking at 80 KTS as well as progressively put the reverser to idle reverse.


Cheers,
SS
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Old 14th Jan 2009, 21:39
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This is not a "1 size fits all". I know what the FCTM says, but airmanship should allow discretion variations. You land on a 3000m runway with turn off that the end. Good weather and no tail wind. Would you set autobrakes? Would you use more than idle REV? If yes to either, why? Please explain. Remember I said airmanship and not SOP's.

I once worked for an airline who did it's own maintenance on brakes & engines. They oscillated between normal reverse and little brakes, to idle reverse and more brakes. They were trying to discover the most cost effective solution. I'm not sure they ever did. Engine & reverser maintenance versus brake pad wear. On cars I was always told it was easier to change nrakes than gear boxes. Brakes were designed for everyday use in slowing down; gear bozes were not. I know it's not the same as reversers and turbines, but there is a significant difference in costs on changing brakes and renovating engines. There is also the difference in carbon or steal brakes; multi short sectors and brake heat.

What about 3 or 4 engine a/c. I've never flown either. Do you guys use all reversers or only 2? Is that an option?

So what is the truth brakes v T/R's? reread para 1.
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Old 25th Jan 2009, 04:36
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I always used all the reversers on 707, 727, and 747. Never worked where we were told how much to use. You just used what you needed.
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Old 26th Jan 2009, 11:35
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I flew many hours in the 737-200 into short runways in the Pacific region. The key was instant reverse on touch down to the FCTM recommended setting (usually 1.6 EPR for passenger comfort since full reverse was really savage with bucket reversers). Providing the approach was accurately flown on speed and threshold height and touch down close to the 1000 ft markers, the brakes were rarely needed until well below 60 knots. This resulted in cool brakes and more brake energy available if an abort was necessary on next take off. There was always the occasional cowboy who liked to show off by applying brakes seconds after touch down as well as reverse. He pulled up quickly but the brakes were too hot to touch during the subsequent pre-flight inspection. With no brake temp gauges it was impossible to tell if the brakes were actually too hot for the next take off. Cowboys were extremely unpopular because of that.

Idle reverse for noise reasons can be a real trap on wet runways and the pilot would look real silly in any subsequent court action if an accident occured due to his failure to use full reverse on a wet limiting runway and instead used idle reverse and max braking. I accept this is generalising because circumstances differ depending on many factors.
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Old 29th Jan 2009, 14:35
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If Noise standards have to be exceeded in case of an emergency.That violation will obviously be ignored.
regds
MEL
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