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More unheard of ideas: NG speed restriction

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More unheard of ideas: NG speed restriction

Old 1st Jul 2016, 00:06
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More unheard of ideas: NG speed restriction

Heard today that the NG is speed restricted to 250kts below 10000ft.

I know that the 756 has a bird strike protection airspeed limitation but the NG?

I just like to energy manage so it would be nice to know as I have regularly flown high speed unless there is a bird race going on.
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Old 1st Jul 2016, 01:36
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Windup alert!
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Old 1st Jul 2016, 01:39
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Think Pin Head is a rather apt name.
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Old 1st Jul 2016, 01:47
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You've got that right.
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Old 1st Jul 2016, 05:52
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ummmm...AFAIK it is well understood that the NG, albeit ALL B models, have a speed restriction of 240 kts below 10K coded in to the system, so the drivers dont blow the check ride. (tailwind?)
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Old 1st Jul 2016, 06:27
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Only in America...
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Old 1st Jul 2016, 07:22
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sorry Bloggs, I think it is a B thing...it was like that on the QF variants...

When doing the coded procedures, set a waypoint at 10K with a speed restriction of 250, that way, (or coming off the STAR) the box would use it for TOD and a continuous descent..AB variants worked fine with this, but the B variants would disco...
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Old 1st Jul 2016, 08:59
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There are multitude of reasons 250/100. Regarding the default 240/100 (B767) I was alway told it was an FAA thing to allow a 10kts overspeed and not bust their ATC limits????

Curious: I flew for one operator (B737) who was on a fuel saving spree. The CI chosen gave 245kts in descent after mach changeover. They still manually entered 250/100. How daft was that??!?
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Old 1st Jul 2016, 09:07
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The Vmo of the 737NG "here" below 10k is 340, as it is with my "little Boeing".
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Old 1st Jul 2016, 09:16
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Hope you don't hit a bird....
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Old 1st Jul 2016, 09:29
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Hope you don't hit a bird....
Huck,
Speaking from experience, there is little difference between hitting a bird at 250KT and 350KT. Fortunately, in my case, neither were Canada Geese.
Tootle pip!!
PS: The actual history of bird strikes (or in the case of TAA, a snake) at high IAS/TAS and high (ish) altitude makes interesting reading.
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Old 1st Jul 2016, 09:33
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Pin head.
You really are a crack up.
Sometimes you have legit questions and sometimes your posts,such as this one just makes me wonder.

If you reach 251 kts on the NG,all spoilers(including ground spoliers) deflect and pitch up is commanded so you dont bust atc speed restrictions and protect yourself from the odds of a bird strike.
Window heat is also increased.
The NG is really top
Avoid flying at high speed for a long time in areas of bird activity is recommended,if the bird is too big you can always duck under
Aircraft management is good,saving gas is even better,high speed is not required for either.
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Old 1st Jul 2016, 09:39
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Underfire Pinhead and Huck, why don't you spend thirty seconds looking in the Limitations section of your FCOM? There is no such limitation if your window heat is working.
This place has been over-run by simmers I fear.
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Old 1st Jul 2016, 10:17
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if the bird is too big you can always duck under!!!!

Not in my airplane,,, we never "duck under a bird",, always over or around as a bird will dive every time from our experience.
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Old 1st Jul 2016, 10:35
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oh my god.
ok,ill rephrase....you can always brace brace brace
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Old 1st Jul 2016, 11:08
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Speaking from experience, there is little difference between hitting a bird at 250KT and 350KT.
...explain that to NASA where a piece of separated FOAM insulation had punctured a hole in the left wing of Columbia.
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Old 1st Jul 2016, 11:24
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To those who fly high speed below FL100.

Much might depend on the environment you are in. It an not be an 'every-time' thing. What do you put in the FMC as XYZ/100? If you left 250/100 and then fly hi-speed it is almost certain you will need speed brake lower down. I always let the F/O's find out for themselves that is the case. I then ask them if they accelerate towards red traffic lights and slam the brakes on or coast in idle towards them?
Various pilots I've known made calculations of a normal VNAV descent from FL200 with 250/100 and a CDA low drag to spool up at 1000': and a 300/100 descent profile. The time saving was miniscule. The stress of "have I got the right?" was removed and any turn radius was much reduced. Being 220kts downwind allowed flaps and a shorter turn-in; saving time. 300kts down wind made for a longer/wider circuit.
There are macho's in a positive manner and there are those in a negative one. It's a good idea to decide which camp you fall in. IMHO.
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Old 1st Jul 2016, 11:24
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Curious: I flew for one operator (B737) who was on a fuel saving spree. The CI chosen gave 245kts in descent after mach changeover. They still manually entered 250/100. How daft was that??!?
Apologies if I am missing the tone in this, but surely that makes sense (albeit over a somewhat pedantic 5kts) as if they leave it alone they will have a decel point at FL100 from 245>240.
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Old 1st Jul 2016, 11:50
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What do you put in the FMC as XYZ/100?
You put in 210/3000 or whatever the limit might be.
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Old 1st Jul 2016, 12:25
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OhNoCB - Point being - If 245kt is optimal for lowest fuel burn, why then increase the speed below FL100?

Rat 5 - I agree with your last point, but was taught it in a different way - Never fly fast away from an airfield...
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