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Hamilton Standard Super-Hydromatic Propellers
Part 4: Super-Hydromatic Propeller Documented Timeline
by Tom Fey
Published 11 Jun 2018; Revised 27 Oct 2023
15 Oct 1941 – Progress Report #1 on first attempt at 50 hour type test. This describes the three blade, twelve foot diameter single rotation Super-Hydromatic propeller on a P&W R-1830 and a description of the mechanism. After 2 hours running, governor found to be low 2 ounces of oil from total capacity of 8 ounces.
20 Oct 1941 – Progress report #2 on first attempt at 50 hour type test. No information was presented, just a letter saying Progress Report #1 had not been received.
5 Nov 1941 – Progress report #3 on first attempt at 50 hour type test. R-1830 push rod failure (at 3 hours) and problems with one vane motor packing found during tear down.
7 Nov 1941 – Progress report #4 Ten hours into first attempt at 50 hour Type Test. Failure of governor drive gearing and excessive oil leakage which stopped test and observation until improved parts can be obtained.
10 Aug 1942 – Planning document saying three Superhdromatic dual rotation prop sets will be needed for the XP-69 (delivery Mar and Jun 1943), two XP-71 twin engine aircraft require six Super-Hydromatics (delivery Dec 1942 and Jun 1943), two XB-35 4-engine aircraft (delivery Nov 1943 and Apr 1944) require twelve dual rotation propeller sets.
Dec 1942 – Roy Fedden Mission to America Report contains a drawing of the Super-Hydromatic propeller
24, 25 Feb 1943 – Photographs of Douglas B-23 with Super-Hydromatic 624060-1 dual rotation props on the port wing.
1943 – Air Tech (month unknown) shows dual rotation Super-Hydromatic on the B-23 test bed; mentions development started in 1938.
Nov 1943 – Popular Science shows photograph of dual rotation Super-Hydromatic on the B-23 in an article about contra-rotating propellers.
7 Jun 1944 – Progress report #2 on third attempt at Model 4260 110 hour type test. Propeller won’t come out of reverse during cycling test.
10 Jun 1944 – Progress report #3 on third attempt at Model 4260 110 hour type test.
13 Jun 1944 – Progress Report #4 on third attempt at Model 4260 110 hour type test.
Jun-Aug 1944 – First flight F4U-1 with dual rotation Super-Hydromatic.
17 Jun 1944 – Progress report #5 on third attempt at the 110 hour Type Test on the 4260 Super-Hydromatic propeller on the R-2800-C power plant.
22 Jun 1944 – Progress Report #6 on the Model 4260 Super-Hydromatic propeller with breakdown of parts and issues. 110 Type Test was passed and report will be written up by Hamilton Standard engineers.
6 Sep 1944 – Requirements for support and transport of dual rotation 828060 propellers are discussed as well as request for clearances for all deicing equipment on this propeller type.
18 Sep 1944 – Letter from Hamilton Standard to ATSC with report of type test.
19 Sep 1944 – Letter from HS to ATSC agreeing to investigate dual rotation 828060 requirements for mounting spinners.
9 Oct 1944 – Description of the mounting requirements for the Model 828060 dual rotation Super-Hydromatic spinners and projections.
12 Oct 1944 – Precise description of the 110 hour type test protocol. Variable power settings and up to 2,800 engine rpm will be tested with frequent cycling sessions (75 to 90 cycles) of the propeller. Will require 2.5 hours at continuous war emergency power (2,400 hp) plus 7.5 hours at intermittent WEP.
23 Oct 1944 – F.C. Macternan of Hamilton Standard describes the Super-Hydromatic propeller during the Joint Fighter Conference, 16-23 Oct 1944, NAS Patuxent River, Maryland.
27 Oct 1944 – Hamilton Standard correspondence to AAF Material Command Data on USN 110 hour type test on the 4260 Super-Hydromatic with 2C15B1-30M propeller blades. Anomalies encountered during and after the successful Type Test were:
Blades – Breakdown and centrifuging outward of rubber pellets bulging two propeller blades. The other two blades used rubber strands, and these performed well, similar to a previous successful 110 hour type test. Blades (rubber strip fill type) performed satisfactory on third attempt at the 110 test. Light to heavy brinnelling of ball races in blade bases and galling between vane motor and prop hub. One vane motor seal failure.
Hub – Loss of 6 ounces prop governor oil per hour which caused hunting during operation. New seals O-rings were installed and surfaces lapped. Bronze shoe on translation linkage and several teeth on the control rack showed wear.
9 Nov 1944 – Superhyromatic propeller will be delivered to Wright Field, Dayton, Ohio the following week.
24 Nov 1944 – Representatives from Hamilton Standard will be in Dayton 28 Nov 1944 to discuss 1) elimination of 24D50 (P-51 type) propeller by summer 1945 to be replaced by the 24D60 propeller ($2,800 unit cost) with 6555A-6 blades and 2) availability of Super-Hydromatic propellers.
20 Feb 1945 – Notations regarding potential for problems with the fillet brazing of Super-Hydromatic propeller blades.
5 Mar 1945 – Air Technical Survey Command (ATSC) specifies which oil is best, at present, in the Super-Hydromatic, but does not recommend all Super-Hydromatics use it until Hamilton Standard completes their evaluation of it.
8 Mar 1945 – Realization that Super-Hydromatic propeller was shipped to Vultee without vane motors.
12 Mar 1945 – Four vane motors sent to Vultee in California.
13 Mar 1945 – First flight of Douglas XTB2D-1 with dual rotation Model 828060 Super-Hydromatic propellers
14 Apr 1945 – Request for additional parts for the Super-Hydromatic to be installed on the C-74 as of 1 Jun 1945. Subsequent response was Douglas only needed mock up parts at this time.
22 May 1945 – Request from Wright Field for electrical deicing equipment for the Super-Hydromatic for testing in NACA icing wind tunnel.
8 Feb 1946 – Hamilton Standard letter regarding report on accelerated flight testing of the 4260-3 Super-Hydromatic on the F4U-1 and F6F-5 (HSP-422). Loss of oil to engine nose case requires seal, but according to Hamilton Standard, this seal affects “the fundamental design of the propeller”, but is being worked on.
13 Feb 1946 – Outline of Super-Hydromatic Test requirements. Description of plan to test P-47M 42-27386 with Super-Hydromatic propeller is model 4260-2C15B3-30 to investigate rapid pitch change operation. Reversing and feathering will not be performed. Expected (future) service life will be 350 hours.
25 Feb 1946 – Request by Army Air Forces Board (General Patterson) for a copy of the Hamilton Standard Service Manual No. 150 for the Super-Hydromatic propeller. Document mailed 13 Mar 1946.
18 Mar 1946 – Test flight of Super-Hydromatic 4260-25 propeller, likely on P-47M 42- 27386, commenced 12 Mar 1946. By 15 Mar 1946 test pilot Paul Burke had put a total of 4 hours 35 minutes on the prop under the said contract.
18 Apr 1946 – Questions regarding whether reversing Super-Hydromatic can be used on the XP-47M. It notes that in-flight reversing of a Curtiss propeller has been achieved.
1 May 1946 – Note regarding: P-47M with Super-Hydromatic blades are unsafe for reverse pitch in flight., but OK for reverse on landing roll. Military desires constant speed control while prop is in reverse. Blades need a rib for sufficient strength during in-flight reversing. Military P-47M test aircraft to have reversing function by Sep 1946.
25 Jun 1946 – First flight of XB-35 with Model 828060 dual rotation Super-Hydromatic propellers
7 Jul 1946 – First and only flight of XF-11 #1 with dual rotation Super-Hydromatic propellers
Nov 1946 – First flight of Ryan XF2R Dark Shark mixed propulsion fighter with a single rotation Super-Hydromatic propeller in the nose.
11 Dec 1946 – Whirl test of Super-Hydromatic 4260-23 propeller and spinner for use on R-2800-22W engine. Note: The R-2800-22 is the engine for the Grumman F7F Tigercat.
1947 – Report RD 1247; Eight blade large diameter number 80-100 shaft size, dual rotation propeller hub for Allison turbine engine.
29 Jun 1951 – Flight Magazine article about 19 foot diameter dual rotation propeller for turbines over 5,000 horsepower. Mentions the Turbohydomatics will be electronically controlled and are based on “… 2,600 hours of flight and ground testing on turbine engine propellers.” Also states that two, 3.5 pound pumps the size of inkwells consume only 15 horsepower to rapidly change the pitch of these very large turbopropellers.
1953 – Hamilton Standard Family Day brochure shows photographs of both single rotation and dual rotation “Turbohydromatic” propellers.
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