Please can you advise (dH propellor)

Taygibay – Could you resize that image a bit please?

900 px wide is plenty

Moggy
Moderator

Miam!

Will keep looking on the side for your prop.

Read you later!
Tay.

It was fun though. We’ll miss you.

Moggy

and I will miss you too….maybe I will take up flying so I can join this fun site….watch out….(you may need to duck) 🙂

It was fun though. We’ll miss you.

Moggy

Tay,Anon, Mr handsome Moggy C and everyone, thank you for your experience and comments.

My father was an aircraft engineer with de Havaland, so it would make sense that he might have received something to do with testing etc, they gave him a gold watch as well. He was a Sikh…brilliant engineer…

I will save your conclusions so I can have it rehearsed word perfect the next time someone asks me.

Shall I take it the mystery ends there? If so, I thank you for your assistance in shedding some light on this. If anyone does think of something else, my email is in my profile I believe. I will keep checking for a time.

Kind Regards to you all
Not entirely a fair lady but a dusky one Tay :)….Sikh and British mix xx

Prop i/d

It certainly looks too short for a flyer. It could have been specially made as a one-off for a specific (unknown) application but my money’s on it being a test club blade.

A standard full-size paddle blade would be cut down to suit different aircraft applications, the blade area being calculated as a function of engine power and RPM.

In a working (i.e., mounted on an aircraft) installation, too big a blade (prop) for a given engine would not allow that engine to achieve its optimum RPM for an expected design thrust. Therefore, it was important that the prop was the right size to make the most of the engine power.

However, for a test prop (club) it is not designed for maximum thrust but to provide a known load on the engine. Max engine power/boost would not be achieved with this prop as this would be determined via other means such as a de Prony brake/dynamometer.

It would just be used to test run an engine for the purposes of setting it up and testing.

Anon.

Hi KarenG, fair lady.
I checked some more on your prop and to tell the truth,
am beginning to reach the end of my wits.

Either one of those proposed earlier or a cut down version
of the paddles seen here :

Cut down of course which may have been for a ground test bed .
I’ll keep looking but I thought I read something about this forum
having a resident propeller blade expert! That would be nice too!

Good day all, Tay.

Thank you

Thank you Tay

Its was in Hertfordshire

Kind Regards Karen

Hi Kareng!
As asked earlier, could you tell us the location of the plant
where your dad worked?

it could really help narrow it down.

Read you later, Tay.:)

The hole should be for pressure equalizing on a hollow blade
but by Jove not drainage, Mylady! Think of it!
Drainage for what? Leaking lube or oil?
What engine will that prop be mounted on anyway?

Sorry for the gust, pray good night to you.

Good night all indeed, Tay.

Drainage for water, for when the plane hits the water Tay, and I climb out from the pilots side. 🙂

I Was just offering as much as possible to help solve the mystery…I know absolutely zero about these things Tay, as you can see ..but thank you

The hole should be for pressure equalizing on a hollow blade
but by Jove not drainage, Mylady! Think of it!
Drainage for what? Leaking lube or oil?
What engine will that prop be mounted on anyway?

Sorry for the gust, pray good night to you.

Good night all indeed, Tay.

Obviously I’ve passed the limit of knowledge (not hard!), so I’ll leave it to those of you who DO have a clue what you are on about. 😮

Adrian

Wanted to add is small hole a drainage hole?

http://commons.wikimedia.org/wiki/File:Helice_HS_54H60-77.JPG

An old one like this?

this is intriguing. I know little about propellers but would they normally have a hole in the end?? (would whistle well!) could this be consistent with John Aeroclubs thoughts that it has been truncated?

Roger Smith.

The miniscule hole is actually on top of the edge of the prop..if you get me
I wondered if it was where the blade was held at one end in manufacturing?? The hole is not all the way through, just 2 millimeters maybe

If you got a pencil and wanted to turn it fast, you might put a hole each end to hold it in place?

Thanks chaps…I appreciate your help.

………..a tiny hole Ive found on the very top part of the propeller in the centre………

this is intriguing. I know little about propellers but would they normally have a hole in the end?? (would whistle well!) could this be consistent with John Aeroclubs thoughts that it has been truncated?

Roger Smith.

I have never seen any lists of serial numbers, and the drwg No is too short to get an identity, but I`m fairly sure it is a right-hand rotation blade which going by the dimensions and look of it appears to be a D-Shank blade which has indeed probably been cropped. The Drwg No beginning 51 would make it a Hamilton Standard. de H blade drawing Nos are prefixed “P”.
If that`s the case it is the type of blade the Harvard / Beech 18 / DHC Beaver etc.
“Anon” is pretty clued up on these things if he appears!

Pete

The loose ring forms part of the bearing, which is inserted when the blade is placed in the hub. All of the bolt holes underneath are consistent with other propellers.

de Havilland had such a wide and varied catalogue of propellers, we need our resident propeller expert to cross reference the numbers we have been given.

We’ll get there!

Bruce

Hello and thanks for your attempts so far to identify it.

It has 2 loose rings on the bottom, one is about half inch in depth and the one above it is about just over half the other one. The rings turn 360 degrees, loose. They cannot be removed and lay above the mould of the base which is bigger and therefore the rings couldn’t possibly slide over it.
You would have to cut them off to remove them. The rings must have been put on while the propeller was being moulded. I think although I dont know how else they could have put them on? No solder type joins on rings.

Underneath there are 4 holes. 2 large and 2 smaller, to fix to something. The two large are opposite each other and the two small likewise. All even in distances apart.

Its very very heavy.

It has that aerodynamic shape that isnt clear in the photo. When you turn it sideways it has that curve that a propeller has, the shapely subtle curvature on it that I have seen on plane propellers before.

The propeller has no visible joins or cuts, its complete in its appearance, you don’t get a look that its been messed with at all. The base looks like it could be attached straight away to something, its not raw.ie, cut off.

Hope this assists you further Thank you

Hard to say from the photo, but I’m not sure that the curvature on the blade is right for a propellor. Might it be a test club (I think that’s the term), for running an engine on a test rig? That might explain the shortness and possibly the width, as it seems quite wide in relation to its length. It might even have been an apropriate presentation for his job….?

Adrian