Halifax propellers

[72modeler]

What an incredible amount of detailed information! What a reference library you must possess, as well as the time it took you to put all of this information into text for all of the interested parties, myself included. Would looking up the prop and blade type provide the diameter, which is the one  dimension most useful to those building Halifax models? Thank you again for your post! 

Mike

[brewerjerry]

6 hours ago, Geoffrey Sinclair said:

........

  This format follows that of the previous Mosquito propeller report .......

Hi

    I missed that, which thread is it in ?

      cheers

         jerry  

[Geoffrey Sinclair]

10 hours ago, 72modeler said:

Would looking up the prop and blade type provide the diameter, which is the one  dimension most useful to those building Halifax models?

It should, but I do not have that information.  Also not so much a great personal library, more specialised.

Plus

[V Line]

On 19/12/2021 at 11:48, Geoffrey Sinclair said:

Ministry of Aircraft Production, Monthly Statistical Bulletin which starts in March 1942, Halifax propeller systems.  Note how the data presented changed over time.  This format follows that of the previous Mosquito propeller report.
 
March 1942
The propeller blade deliveries table starts in January 1941, wooden blades start in November 1941.  Metal blade forgings are from De Havilland and Rotol, with De Havilland dominating the output. Propeller for Halifax is the Hydraulic Rotol 3 blade including the constant speed unit.
 
Repaired propellers are categorised as Fixed Pitch Wooden, Fixed Pitch Metal, Two Pitch, Constant Speed Cam, Constant Speed Hydraulic De Havilland, Constant Speed Hydraulic Rotol, Constant Speed Electric (but none until March 1942), American two pitch, American Cam, American Hydraulic, American Electric, first US propeller repairs in July 1941.
 
April 1942,
Blade deliveries table now has factory information, De Havilland Lostok producing in January 1941, Stag Lane began production in July 1941, Wooden blades by Rotol.  Blade forgings, De Havilland are Dural, Rotol are Dural (starting February 1941) and Magnesium, Fairey fixed pitch Dural from January 1941. Thrust bearing (blade sets), De Havilland and Rotol from January 1942, Wooden blade root adaptor production begins in November 1941.
 
Hub forging and Weldings, De Havilland Cam Spiders and Cam Barrels, Hydromatic Spiders and Hydromatic Barrels from January 1941.  Rotol Hydraulic 3 blade forgings from January 1941, Weldings from December 1941, Hydraulic 4 blade, 198 forgings produced to end February 1942, 58 Weldings in March, Electric forgings from April 1941.

Repairs now amalgamate the British Two Pitch and Constant Speed Cam figures, plus the American Two Pitch and Cam figures.
 
August 1942,
Propeller for Halifax II is the Hydraulc Rotol 3 blade including the constant speed unit. (mark number given for first time.)
Rotol ceases Magnesium blade forging production.
Barrel Set delivery figures recalculated, previously they were unmatched "front" and "rear" barrels.  USA 3 blade hydraulic forgings have been in figures since January 1942, broken out as a note to the table for the first time in August.
 
September 1942
Propeller for Halifax II is the Hydraulic Rotol 3 blade including the constant speed unit.

Table for Propeller stocks at Aircraft Contractors or awaiting repairs added.  Rotol Hydraulic for Halifax I, II, V, 494 at contractors, 41 under or awaiting repairs.

Table for Constant Speed Unit stocks at Aircraft Contractors or awaiting repairs added.

Table for New Propeller production by types added, from June 1941, Fixed Pitch Wood, Fixed Pitch Metal, Constant Speed Cam, Constant Speed Hydraulic De Havilland, Constant Speed Hydraulic Rotol 3 Blade, Constant Speed Hydraulic Rotol 4 Blade (from November 1941), Constant Speed Electric.
 
Table for New Propeller production by firms added, from May 1941, firms are De Havilland Stag Lane, De Havilland Lostock, Rotol No.1 Shadow (production from July 1942), Fairy (production from June 1941), Hordern Richmond (production from June 1941), Bath Aircraft (production August 1941 to April 1942, then a pause until October), Airscrew Company (production from June 1941),
 
Table for New CSU production by firms added starting in May 1941, De Havilland Cam, De Havilland Hydromatic, Rotol 3 Blade, Rotol 4 blade (from December 1941), Electric
 
Table for Assembly of USA propellers in UK added, data starting in December 1941, Stag Lane Warwick I, Lostock Lancaster I from July 1942, Stag Lane Stirling II from September 1942.
 
October 1942
Hoover added to firms producing propellers, first production in October. Bath Aircraft resumes propeller production.  Fairey fixed pitch Dural blade figures from January 1941 deleted as inaccurate. Rotol ceases Dural Blade forgings, except for a batch October/November 1943.

 

November 1942
Assembly of US propellers is now cumulative totals.

 

December 1942,

Propeller for Halifax II and V is the Hydraulc Rotol 3 blade including the constant speed unit.

New CSU production table is now De Havilland Cam, De Havilland Hydromatic small, De Havilland Hydromatic large, Rotol Hydraulic Feathering, Rotol Hydraulic Non Feathering, Electric.
 
January 1943,

Assembly for USA propellers has CSU data added.  Table for delivery of Propeller Hub Forgings and Hub Weldings dropped.

Production of New Propellers for the Month adds type/model number field, Propeller for Halifax II and V is the Hydraulc Rotol 3 blade including the constant speed unit, various types.

Production of Constant Speed Units for Month adds type field, Rotol Hydraulic for Halifax II, V type GRF/I (same as Wellington IV, Whitley and Spitfires have GRF, Beaufighter II GRF/IA)
Under repair list has Halifax, Wellington VI and Whitley figures grouped together.
Halifax III propeller Hydromatic De Havilland 3 blade model 55/18, spinner large Hydromatic De Havilland AY 6 (Same as Stirling III and various Wellington and Beaufighter marks)

 

February 1943,
Constant Speed Cam propellers redesignated Constant Speed Bracket.  Vickers Armstrong now making propellers.
 New Table, CSU production by firm, starting in December 1942, De Havilland Stag Lane, Rotol Gloucester, Rotol Worcester, Standard, Gillette, No. 1 Shadow.

 

March 1943,
CSU by firm revised, De Havilland types made by De Havilland and Standard, Rotol types made by Rotol Gloucester, Rotol Worcester, Standard, Gillette, No. 1 Shadow.

 

April 1943,
Spinner production table added.  Halifax II, V Hydraulic Rotol 3 blade.  Constant Speed Unit GRF/I now for Halifax II, V and Whitley V.

 

May 1943
Two new tables, starting from November 1942, Spinner production by type, De Havilland Bracket, De Havilland Hydromatic 3 blade, De Havilland Hydromatic 4 blade, Rotol Hydraulic 3 blade, Rotol Hydraulic 4 blade, Rotol Hydraulic 5 blade, Rotol electric.
Also New Spinner production by firm, De Havilland types from C.S.A, De Havilland types from Sankey, Rotol types from Rotol Gloucester, Rotol types from C.S.A., Rotol types from Sankey.

Constant Speed Units for Halifax II, V and Whitley V now GRF/I, GR/4  (Possibly GRF/4?)
Under repair list has Halifax, Wellington VI and Whitley figures grouped together using type GRF/I.

 

June 1943,
Standard added to firms making propellers, first production in June.

 

July 1943
New type of propeller being made, the Rack.

 

September 1943,
Halifax III, B.VI propeller Hydromatic De Havilland 3 blade model 55/18

 

October 1943,
Halifax B.II, V Hydraulic Rotol 3 blade. (appearance of aircraft designator letter)  Same in spinner and propeller stocks tables (1, B.II, V in the latter).

 

December 1943,
Halifax B.II, V now also Hydraulic Rotol 4 blade, no model given, B.II, V still "various".  Spinner Hydraulic Rotol 4 blade.

 

January 1944,
Standard ceases propeller production.
 
March 1944
Templetons is added as maker of De Havilland propeller blades, staring in January 1944, in April 1944 the report has Templetons production beginning in May 1942, previously counted under Lostock.

 

April 1944,

3 blade Rotol propeller production for Halifax ends.  Rotol Gloucester ceases CSU production.

 

May 1944,
Halifax III, B.VI propeller Hydromatic De Havilland 3 blade model 55/18, 55/19.  Shadow factory No.1 ceases CSU production.

 

June 1944,
Propeller stocks report say the Hydraulic Rotol 4 blade propellers for Halifax B.II, V are types R7/4, B5/4.

 

July 1944
Rack propeller production ceases.

 

August 1944,
Halifax III, B.VI, B.VII propeller Hydromatic De Havilland 3 blade model 55/1, 55/19.
Rotol begins production of 2 blade hydraulic constant speed propellers.  Hordern Richmond cease propeller production until December.

 

September 1944,
Bracket propeller production ceases as does CSU units for them.

 

October 1944,
Propeller stocks report say the Hydraulic Rotol 4 blade propellers for Halifax B.II, V are types R7/4B5/4, R34/4B5/4
Number 1 Shadow factory ceases propeller production.

 

November 1944,
Halifax B.II, V propeller Hydraulic Rotol 4 Blade, R7/4B5/4,
Halfax III, B.VI, C.VI, B.VII, C.VII propeller Hydromatic De Havilland 3 blade, 55/18, 55/19.

 

December 1944,
Rotol ceases 3 Blade Hydromatic constant speed propellers.

 

January 1945,
Rotol 4 blade propeller production for Halifax ceases.  Hoover ceases propeller production.

 

March 1945,
Double Acting CSU monthly production begins (20 have been built in May and 1 in October 1944)
Gillette CSU production ceases as does electric CSU production since Gillette was the sole UK maker of electric CSU.

 

April 1945,
Contra rotating propeller production begins.

 

August 1945,
De Havilland ceases propeller production for Halifaxes and AY 6 constant speed unit.  Stocks reports discontinued.

 

September 1945,
Fairey and Hordern Richmond cease propeller production.  Electric propeller production ends?  US propeller table dropped.
 
October 1945,
De Havilland 3 blade, hydraulic constant speed propeller production ends?  And De Havilland large Hydromatic CSU unit production ends?

November 1945,  End of reports.

 

Geoffrey,

Your narrative is, as usual, comprehensive and educational. The business of propeller production was large, complex and pressurised.

 

I cross referenced the report extracts against the data I have.

 

AY6 is a governor not spinner –used on a number of Hercules powered Stirling, Beaufighter Wellington and Halifax types.

 

I do not believe spinners were used on Halifax dH hydromatics at any point (two types for Rotol). Spinners were however fitted to some hydromatics used on the Stirling, Beaufighter, Wellington and Lancaster.

 

I can find no reference whatsoever to Rotol Dural blades for Halifax aircraft although there were two magnesium blade types which I suspect were probably phased out by mid-war.

Regarding Halifax 4 blade propeller types, there was a certain amount of re-designation going on and I believe there were only two variants. Each used blades which were also found on some 3 blade types:

 

R34/4B5/4(formerly R7/4B5/4)-RA 682 – 13ft diameter

R34/45B/5- DB 1140—12ft 9ins diameter

 

I have no dates for this but it seems the Merlin versions were phased out in favour of Hercules variants by war’s end. The 1945 and post-war Halifax and Halton were Hercules/dH fitted.

 

Prompted by the O.P. I had a particular reason to look at this aircraft’s 3 blade prop listings and as it’s Christmas    😊     I will share them with readers of this thread:

 

Rotol (Merlin) RH Rotation

Dia

13ft –RA682 (Also used on Whitley)

12ft 9ins-DR1140 (also used on Whitley)

12ft – RA4071 (also used on Whitley)

12ft 6ins- RA10041 (Magnesium)-different spinner to above

12ft 6ins- RA4041 (Magnesium)-ditto – (I believe this to be the first blade used on production aircraft-see below second prototype).

 

 

de Haviland (Hercules) LH Rotation

 

I believe only two types, both of 13ft diameter (although some constructional detail variations indicated by ‘dash numbers.’)

 

P4551169A

P4551775A

 

The PX.500 hub assembly in @canberra kid’s post above was used on Halifax Hercules VI, XVI and 100-Prop types 55/18, 55/19 and 55/19a. Blades P4551169A-17, P45517775A-17,ditto, respectively.

 

There were several additional prop (hub) types but for the modeller the main focus will be the blade element.

 

In the absence of blade drawings, measurements or originals for comparison it can be very difficult to identify prop blades in contemporary photographs (even assuming one can be found).

 

As an example, Spitfire 1 to V dH types are straightforward as there were only two! By contrast Hurricane Rotols are less easy. From 1941 there was an increasing number of variants, further complicated by some of same types having different style blade tips. Then you have the common factors of camera angles, perspective, pitch positions etc.

 

I have not been able to distinguish between blades shown on photos of Hercules engined Halifax aircraft. Assuming the photos I examined included both types one assumes there is little visual difference at scale.

 

Nevertheless, the drawing numbers were different and grappling with the dH blade numbering system it seems that the ‘77A’ was a shorter variant of the late Short Stirling blade. The ‘69A’ was a longer version of the later Wellington blade. Both were ‘flared’ or ‘semi flared ‘ (‘paddlebade’ in US speak).   

 

Photo of Friday the 13th and crew to finish.