ATC requests cloud tops at night
Joined: Nov 2013
Posts: 171
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From: United States
Oh OH!!! I know the answer to this one....
How to calculate cloud tops with wx radar...
(But you will have to depressurize the airplane)
Remove the radar display unit from the panel (although you may need to sneak a screwdriver on board because pilots aren't allowed to have screwdrivers).
Toss the unit out the window and start the timer...
When your unit disappears into the cloud tops, stop the timer...
Use the terminal velocity formula, v = the square root of ((2*m*g)/(ρ*A*C))
The rest is pretty academic.
(This really works by the way but I had to quick Google that last part)
How to calculate cloud tops with wx radar...
(But you will have to depressurize the airplane)
Remove the radar display unit from the panel (although you may need to sneak a screwdriver on board because pilots aren't allowed to have screwdrivers).
Toss the unit out the window and start the timer...
When your unit disappears into the cloud tops, stop the timer...
Use the terminal velocity formula, v = the square root of ((2*m*g)/(ρ*A*C))
The rest is pretty academic.
(This really works by the way but I had to quick Google that last part)
Joined: Apr 2008
Posts: 309
Likes: 0
From: .
That's probably how Nemrytter does it, I guess. Clever chap.
As someone said on the last page: It's "impractical." But it's not impossible.
Guest
Posts: n/a
There are always those who enjoy to confuse apples with bananas.
The thread subject is: "ATC requests cloud tops at night "
and not: ATC requests TO CALCULATE cloud tops at night.
All that ATC wants in this case is:
Pilot Visual report, using Pilot cockpit windows vs Pilot altimeters, during climb or descent. During level flight just say you are bellow,above or on top.
PS
If you can not make the difference between night-sky
(with or without moon, the darker the more stars should be there ! )
opposite to no-sky-visible due to in-cloud conditions then no calculation will help you.
The thread subject is: "ATC requests cloud tops at night "
and not: ATC requests TO CALCULATE cloud tops at night.
All that ATC wants in this case is:
Pilot Visual report, using Pilot cockpit windows vs Pilot altimeters, during climb or descent. During level flight just say you are bellow,above or on top.
PS
If you can not make the difference between night-sky
(with or without moon, the darker the more stars should be there ! )
opposite to no-sky-visible due to in-cloud conditions then no calculation will help you.

Thread Starter
Joined: Apr 2008
Posts: 1
Likes: 2
From: nowhere
It did not appear to be a night of any buildups. There was midlevel cloud below with very little but some light with no real depth perception. I will say that we were flying over an area where public TV had said would have rain on the ground.




