<VV> Gas freezing?

[Ron]

The Pratt & Whitney and, I assume Air Force, Standard Atmosphere Table 
gives -69.7 F at 50,000 feet for design purposes.  At 20,000 feet it's -12.3 
F.  No rules of thumb are accepted by the USAF.
RonH

----- Original Message ----- 
From: "J. R. Read" <hmlinc at sbcglobal.net>
To: <virtualvairs at corvair.org>; <aeroned at aol.com>
Sent: Wednesday, December 25, 2013 4:47 PM
Subject: <VV> Gas freezing?


> Sorry, I'll try to be more clear on my calcs.  Starting with 70F at sea
> level and using the "rule of thumb" (strange expression) of a drop of 3F 
> for
> each 1,000 feet of altitude, the temp at 50,000 feet would be around -80F.
>>From sea level to 50,000 at 3F per 1,000 feet the temp will drop by 150F 
>>or
> so.  Subtracting the 70F at sea level, you end up at -80F at 50,000.  If 
> the
> rule of thumb is off a bit from the 3F drop, then the appropriate 
> adjustment
> needs to be made.
>
> Once again - not a real likely altitude for a piston engine, but even 
> 20,000
> feet would give you a temp around +10F and little air for breathing or the
> engine.  I think that we are in agreement that freezing fuel would not be
> the main problem.
>
> Later, JR
>
> ----- Original Message ----- 
> From: <aeroned at aol.com>
> To: <virtualvairs at corvair.org>
>
> Sent: Wednesday, December 25, 2013 12:30 PM
> Subject: Re: <VV> Non-Corvair Specific: Gas freezing?
>
>
>>
>> OK JR, at 50000 feet it's -69F not quite -97 or -80 but I suppose it's
>> close enough?
>>
>>
>> -----Original Message-----
>> From: J. R. Read <hmlinc at sbcglobal.net>
>> To: virtualvairs <virtualvairs at corvair.org>; aeroned <aeroned at aol.com>
>> Sent: Tue, Dec 24, 2013 10:11 am
>> Subject: Re: <VV> Non-Corvair Specific: Gas freezing?
>>
>>
>> Probably more like 50,000 feet.  Still a problem.
>> Later, JR
>>
>> ----- Original Message ----- 
>> From: <aeroned at aol.com>
>> To: <virtualvairs at corvair.org>
>> Sent: Tuesday, December 24, 2013 9:47 AM
>> Subject: Re: <VV> Non-Corvair Specific: Gas freezing?
>>
>>
>>>
>>> I don't know where Matt's flying his piston aircraft, but -80F would be
>>> up
>>> around 250,000 feet (outer space).
>>> http://www.engineeringtoolbox.com/standard-atmosphere-d_604.html
>>>
>>> At that altitude freezing gas would be the least of your troubles.
>>>
>>> Ned
>>>
>
>
> ---
> This email is free from viruses and malware because avast! Antivirus 
> protection is active.
> http://www.avast.com
>
> _______________________________________________
> This message was sent by the VirtualVairs mailing list, all copyrights are 
> the property
> of the writer, please attribute properly. For help, 
> mailto:vv-help at corvair.org
> This list sponsored by the Corvair Society of America, 
> http://www.corvair.org/
> Post messages to: VirtualVairs at corvair.org
> Change your options: 
> http://www.vv.corvair.org/mailman/options/virtualvairs
> _______________________________________________
>