aircraft doomed if takeoffs with maxthrust and encounter windshear?
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And assuming you're at the max weight applicable for that OAT?
Not necessarily - you're some knots above stick-shaker which
translates into an increase in climb capability. Also your balls
to the wall thrust is most likely higher than what you set on
the EPR or N1 gages.
If its a bad day and you lose a donk in the process....well its
a different story then.
Not necessarily - you're some knots above stick-shaker which
translates into an increase in climb capability. Also your balls
to the wall thrust is most likely higher than what you set on
the EPR or N1 gages.
If its a bad day and you lose a donk in the process....well its
a different story then.
If ANY aircraft ever encounters windshear which is beyond it's ability to out-climb, it's a gonner.
Clearly operating closer to the aircrafts maximum performance gives you less margin- but where do you draw the line?
There are buffers built in to takeoff peformance so even a takeoff needing TOGA thrust leaves excess performance that can be used if needed.
ETA- Post crossed with the Slash, who is correct.
Take-off performance allows for an engine failure- so provided both keep running, you have that much excess performance to counter windshear.
Clearly operating closer to the aircrafts maximum performance gives you less margin- but where do you draw the line?
There are buffers built in to takeoff peformance so even a takeoff needing TOGA thrust leaves excess performance that can be used if needed.
ETA- Post crossed with the Slash, who is correct.
Take-off performance allows for an engine failure- so provided both keep running, you have that much excess performance to counter windshear.
Last edited by Wizofoz; 6th May 2013 at 04:50.
Precisely - there's no 'maybe' about it.
U
U
If significant windshear is anticipated, reported or likely, I'd be using ground idle thrust at the worst.
Windshear recovery procedures.
Depends on windshear severity.
what kind of recovery procedures can it apply?
aircraft doomed if takeoffs with maxthrust and encounter windshear?
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Slasher Hell why don't we just stop teaching windshear recovery then.
If you already have the engines at max then you can check off that part of the checklist and follow the rest of the items with less worry about spoolup times.
One is not doomed just because they have already met one of the checklist requirements, just carry on with flying
I miss Slasher already
One is not doomed just because they have already met one of the checklist requirements, just carry on with flying
I miss Slasher already
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aircraft doomed if takeoffs with maxthrust and encounter windshear?
what kind of recovery procedures can it apply?
Bend over, head between legs and kiss your a@Łe goodbye.
what kind of recovery procedures can it apply?
Bend over, head between legs and kiss your a@Łe goodbye.
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Depending upon whose operations manual you use, some state that if severe windshear is forecast, DO NOT TAKE OFF.
If it isn't forecast and you encounter it, do as some of the previous posters suggest and you'll have a fighting chance.
If it isn't forecast and you encounter it, do as some of the previous posters suggest and you'll have a fighting chance.
Had it once on a md 80 off 34 zrh..
Not forecast but mate reported it just before we departed - he was airborne off 28.- 23 knots cross.
We lost 30 knots around 1000ft but had a significant temperature increase..which meant we were way outside our take off calculation.
Went firewall and pitch but speed continued to decrease and therefore on the backside of the drag curve.
Skipper ignored my speed calls and with the black forest looming in the darkness I forced the nose down...and we started accelerating. Climb performance slowly returned.
Cause large pool of very cold air over the airfield but a warm front blowing over the top.
Besides one partial report no forecast to stop us going.
Not forecast but mate reported it just before we departed - he was airborne off 28.- 23 knots cross.
We lost 30 knots around 1000ft but had a significant temperature increase..which meant we were way outside our take off calculation.
Went firewall and pitch but speed continued to decrease and therefore on the backside of the drag curve.
Skipper ignored my speed calls and with the black forest looming in the darkness I forced the nose down...and we started accelerating. Climb performance slowly returned.
Cause large pool of very cold air over the airfield but a warm front blowing over the top.
Besides one partial report no forecast to stop us going.
Last edited by blind pew; 7th May 2013 at 17:37.
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Windshear is fairly predictable. Once in a while you have to deal with it when unexpected. Just be ready and know how to deal with it. You never use anything but max power with possible wind shear. We did the procedure all the time in the sim, never had it happen in real life.
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I've hit it twice on landing. Full power, pitch just above stall, engines screaming and the plane is going down. Hit hard both times.
Much of this depends on the severity, your altitude, engine spool up time, and how much excess power you can throw in. A little twin only has so much. A jet that can throw in enough for an initial 10k FPM climb is better.
That said, this is ALL about hand flying by the way. My suspicions are a few guys have stalled the aircraft rather then mush in and take the hit if they have to.
Much of this depends on the severity, your altitude, engine spool up time, and how much excess power you can throw in. A little twin only has so much. A jet that can throw in enough for an initial 10k FPM climb is better.
That said, this is ALL about hand flying by the way. My suspicions are a few guys have stalled the aircraft rather then mush in and take the hit if they have to.