Aviation Unison?

[carlteplitski]

Many years ago I had occasion to tune for a lady who was a war bride of a 
Canadian soldier,
and came to live in our country with her husband.  I was tuning in the bass 
of her large upright,
when she made the remark that the piano sounded like an squadron of planes 
going over England
in 1942. She said that they got to know if the planes were friendly or enemy 
by the sound. This
coming from untrained ears , who didn't know about beats, etc.   I was 
facinated by her remark,
and made me pay much closer attention to what I was hearing. Tuning unisons 
became much more
meaningful.  I don't suppose Jets have  similar characteristics, or do they 
??

Carl / Winnipeg.


----- Original Message ----- 
From: "Alan Barnard" <tune4u at earthlink.net>
To: <pianotech at ptg.org>
Sent: Thursday, August 02, 2007 5:25 PM
Subject: RE: Aviation Unison?


> That's how aircraft engines were synchronized before they had computers to 
> do it. A B29 pilot, for example would start one engine, then start the 
> second and sync it to no beats by adjusting throttles, mixture, prop 
> pitch, whatever, then the third, then the fourth. Otherwise the engines 
> are "unequally yoked", as it were, and aren't as efficient and put torque 
> stresses on the wings, I would think.
>
> Alan Barnard
> Salem, MO
>
> ----- Original message ----------------------------------------
> From: david at piano.plus.com
> To: pianotech at ptg.org
> Received: 8/2/2007 2:17:23 PM
> Subject: Aviation Unison?
>
>
>>As the Airbus 320 taxid gently to the runway yesterday at Philadelphia
>>(flying GlasgoW-Philadelphia-San Francisco-Redding), sitting in an aisle
>>seat over the wings,  I could hear the beat rate between the engines slow
>>down and speed up as their respective revs changed slightly.  For a few
>>seconds, they would slow to almost unison.  Those who sing will know the
>>phenomenon where, listening to a singer, one feeels one's throat and body
>>tense in sympathy.  On that plane, my left arm (i tune left-handed) was
>>itching to move something with a tuning lever, to achieve unison!
>
>
> -- 
> No virus found in this incoming message.
> Checked by AVG Free Edition.
> Version: 7.5.476 / Virus Database: 269.11.2/933 - Release Date: 8/2/2007 
> 2:22 PM
>