Angels and Demons
Joined: Aug 2007
Posts: 69
Likes: 0
From: Between East and West Poles.
Converter Program
I found a converter program on the internet. It is Freeware. Go to the Google website and put in Joshua F Madison Convert and you will then find and download the program. It has 17 different items, Force, Light, Mass, Speed, Power are some of what is there.
A very nifty program that I recommend you to try.
I hope that this is not advertising that upsets the Moderator. !!!
A very nifty program that I recommend you to try.
I hope that this is not advertising that upsets the Moderator. !!!
Joined: Sep 1999
Posts: 5,552
Likes: 25
From: ME
mach 15 at 60000 feet - Wolfram|Alpha
Gives the answer as 8614 kts
and 9990 kts at Sea Level...
Mutt
Gives the answer as 8614 kts
and 9990 kts at Sea Level...
Mutt
Joined: Jun 2001
Posts: 4,369
Likes: 3
From: UK.
My Computer Dead Reckoning MK. 4A. by The London Name Plate Mfg. Co. Ltd.
using a cor. OAT of -56.5 and M15 gives 8560kn.
First time it's been used >M1.0 - poor thing looks quite worn out.
Correcting for radial change at 60000' gives 8535kn over the ground in still air.
Anyhoo, at M15 with a DT of about 9650C, speed would be the least of his problems.
using a cor. OAT of -56.5 and M15 gives 8560kn.
First time it's been used >M1.0 - poor thing looks quite worn out.
Correcting for radial change at 60000' gives 8535kn over the ground in still air.
Anyhoo, at M15 with a DT of about 9650C, speed would be the least of his problems.
Moderator
Joined: Feb 2000
Aviation Qualifications: CPL
Posts: 14,480
Likes: 178
From: UK
Indicated, calibrated and equivalent airspeed are irrelevant here, we can convert directly from mach number to true airspeed.
The standard formula for the speed of sound is SQRT (Gamma x R x T)
Gamma for a diatomic gas such as air pretty much is, is 1.4
R, specific (something or other) for air, is normally quoted at 287 J/kg.K [sorry, I'm doing this from memory, I can remember the values but not the full name of the constant.]
T is in this instance fairly easy, it's the air temperature. Whilst layers vary a bit with conditions, you can reasonably assume that the aircraft(!) is in the lower stratosphere, which ISA quotes as a constant temperature layer at -54deg.C - 219.15K.
So SQRT (1.4 x 287 x 219) = 297 m/s
At Mach 15 then, this gives you 297 x 15 = 4,450 m/s
To convert m/s to knots: 1 m/s = 1.94kn.
So, Mach 15 in the lower stratosphere is 8,632 knots TAS (True Air Speed).
Well into the lower statosphere, you're well above most winds, which tend to exist primarily in the troposphere, and even the jetstream which sits around the tropopause (typically 30-50,000ft) so by and large TAS = G/S.
So, M=15 @ FL600 gives you about 8,632 kn (or 9,944 mph).
G
(Currently writing a chapter of a book on high altitude aerodynamics for a European Comission study group on high altitude UAVs).
N.B. I made the mistake of buying the audiobook of Angels and Demons for a long drive. Utter and total drivel I thought - is the film any better or worse?
The standard formula for the speed of sound is SQRT (Gamma x R x T)
Gamma for a diatomic gas such as air pretty much is, is 1.4
R, specific (something or other) for air, is normally quoted at 287 J/kg.K [sorry, I'm doing this from memory, I can remember the values but not the full name of the constant.]
T is in this instance fairly easy, it's the air temperature. Whilst layers vary a bit with conditions, you can reasonably assume that the aircraft(!) is in the lower stratosphere, which ISA quotes as a constant temperature layer at -54deg.C - 219.15K.
So SQRT (1.4 x 287 x 219) = 297 m/s
At Mach 15 then, this gives you 297 x 15 = 4,450 m/s
To convert m/s to knots: 1 m/s = 1.94kn.
So, Mach 15 in the lower stratosphere is 8,632 knots TAS (True Air Speed).
Well into the lower statosphere, you're well above most winds, which tend to exist primarily in the troposphere, and even the jetstream which sits around the tropopause (typically 30-50,000ft) so by and large TAS = G/S.
So, M=15 @ FL600 gives you about 8,632 kn (or 9,944 mph).
G
(Currently writing a chapter of a book on high altitude aerodynamics for a European Comission study group on high altitude UAVs).
N.B. I made the mistake of buying the audiobook of Angels and Demons for a long drive. Utter and total drivel I thought - is the film any better or worse?
