View Full Version : Identification Help required

02-10-2014, 01:32 PM
Dear Propeller experts

I have a propeller with no provenace or information.

I have taken down a few details to assist and attached some images.

P5 7 – Pitch of Propeller
D7 5 – Diameter of Propeller

DRG NO IY 756/3 –Blue print for manufacture of propeller

Lynx IV ABC Star – Armstrong Siddeley Lynx IV engine. Used on the Avro 504 N variant?

230cm long

Dark wood

8 bolt holes

Offset blade patterns

Fabric covered tips

Any help with identification would be much appreciated.

Many thanks


02-10-2014, 06:49 PM
AVRO Prefect - listing here (http://www.woodenpropeller.com/Britishprops.htm). Note the left hand rotation of the prop.



(Moved to "Modern Wooden Propellers" category.)

Bob Gardner
02-11-2014, 02:03 AM
Greetings Ed,

The drawing number Y756 (where Y indicates an Avro designed prop) was used on both the Avro 504N and the Avro Tutor, both RAF basic training aircraft. The Avro Prefect was a variant of the Avro Tutor designed for and used by about 18 foreign countries and British Empire countries. It almost certainly used the prop Y756 where the engine was the Lynx IV.

The drg no I/Y756 is the only example that I have seen where the I/ prefix is used and I don't know what it means. Four examples of the Prefect were sold to Eire, so it is remotely possible that I indicates Ireland.

Another peculiarity is the wording ABC Star. I don't know why this should be stamped on this prop. ABC is the acronym for the All-British Engine Company co-founded by Granville Bradshaw during WW1 which produced the ABC Dragonfly engine which was of very advanced design and promised a considerable increase in power. 11,000 were ordered but the engine was a disastrous failure and was quickly cancelled.

Bradshaw also designed and flew the Star aircraft around 1910 and started the Star Aircraft Co.

But what this tenuous connection has to do with Avro's Prefect or Armstong-Siddeley's Lynx I know not!

With kind regards,


02-11-2014, 08:42 AM
Bob, I noticed the IY prefix on the table linked to above (which I believe you kindly provided to the forum years ago).


It does specify the Prefect as the only application for that specific drawing number. I'll defer to your guess as to why . . .