Indicated airspeed with a tailwind
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From: greece
Indicated airspeed with a tailwind
Hi ,
If i am in an approach with an indicated airspeed of 70 knots and we encounter a tailwind of 70 knots or more for any reason ,i know my ground speed will increase to 140 knots or more.
Will i stall and lose lift suddenly due wind opposing and destroying the laminar airflow over the wing with a constant indicated airspeed of 70 knots or my indicated airspeed will drop and then we stall ?
If it drops , why ? Shouldnt the IAS remain constant with a tailwind ?
Thanks in advance .
If i am in an approach with an indicated airspeed of 70 knots and we encounter a tailwind of 70 knots or more for any reason ,i know my ground speed will increase to 140 knots or more.
Will i stall and lose lift suddenly due wind opposing and destroying the laminar airflow over the wing with a constant indicated airspeed of 70 knots or my indicated airspeed will drop and then we stall ?
If it drops , why ? Shouldnt the IAS remain constant with a tailwind ?
Thanks in advance .
Joined: Feb 2001
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From: The Winchester
Oh no....not the downwind turns thread again......
Really important bit- assuming this is rapid change of wind velocity - how long is going to take for you to recover your groundspeed?
What is going to happen to your airspeed in the meantime...and what could the consequences be?
As DR has said, think inertia/momentum.
If i am in an approach with an indicated airspeed of 70 knots and we encounter a tailwind of 70 knots or more for any reason ,i know my ground speed will increase to 140 knots or more.
What is going to happen to your airspeed in the meantime...and what could the consequences be?
As DR has said, think inertia/momentum.
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From: Dog House
I was driving my car the other day into a 50km head wind at a speed of 100km/h, suddenly the wind changed 180 degrees at this point and 5 seconds later what is my new cars speed per hour?
a)100km/h
b)150km/h
c)200km/h
x) my car is accelerating from 100km/h to a higher speed
a)100km/h
b)150km/h
c)200km/h
x) my car is accelerating from 100km/h to a higher speed
Joined: May 2005
Aviation Qualifications: PPL
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From: Denmark
If the wind abruptly changes from calm a 70 knot tailwind:
Ground speed will remain at 70 kts, however increasing for as long as it lasts.
Airspeed will abruptly drop to zero, and you shall drop from the sky as a grand piano with a closed lid.
Ground speed will remain at 70 kts, however increasing for as long as it lasts.
Airspeed will abruptly drop to zero, and you shall drop from the sky as a grand piano with a closed lid.
Joined: Jun 2005
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From: USA
please explain your comment.
An old thread and global phenomenon. Where physics defy understanding for many. Especially when people keep altering the original premise of the argument! (As they tend to do in such arguments) Anyway it's a fun thread.
Back to instantaneous force vectors...
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From: Here and there
What you have is a an incredibly strong decreasing performance windshear and you will lose all of your airspeed (or lots of it, depending on how abrupt the change is). The following crash will be spectacular.
Note this has nothing to do with downwind turns as that scenario assumes a steady airmass while the OP's example has an abrupt change in the airmass.
