Re: The Rumble of Thunder in the Sky, 1HP per LB

Date:         19 Feb 98 01:34:45 
From:         Krister Engvoll <>
Organization: The Norwegian University of Science and Technology
References:   1
Next article
View raw article
  or MIME structure

National Aero Safety wrote:

> (By comparison with Liquid cooled in-line, or "V"-in-line Aero Engines,
> there is NO COMPARISON!  The Allison V-1710-G6 weighs approximately
> 1,600 Pounds(717kg), and produces only 1,250 HP.  The Rolls Royce Merlin
> is roughly the same weight and produces only 30 HP more.

I too am a great fan of large radial engines, and precious few sounds are
greater than that of a big radial engine.
I will never forget when I was sleeping out in the open ( protesting the
then ridicolous room charge) at a (very) small Norwegian glider airstrip,
and was awakened at dawn by a T6 lowpass. Mmmm... Few girls have ever bested
that performance...

But , you are wrong in your comparison to other engines.
The Merlin 61 that powered the mk9 produced 1535hp and the Griffon 65
powering late war Spitfires
(mk14?) could wring out more than 2000hp, I believe it weighed some

The inline H-engines from Napier-Sabre were good for 2800hp, but I do not
remember their weight, certainly far less than the radials. Hawker Tempests
flew these.

All in all, if you compare engines from the same time, I think you will find
they have similar power to weight ratio.

And for the record: No engine ever sounded better than the RR Merlin, the
big radials are a close second.

BTW. As for Lycoming it is no wonder they could not make it work, when they
in the 50 years since have not managed to to come up with better GA engines
than the O-200,320,360,540 crap.

Krister Engvoll
Laboratoriet for Radiologisk Datering
Sem Sælandsvei 5
7034 Trondheim