The Lycoming XR-7755
Contracts/Administrative Chronology, 1945
by Kimble D. McCutcheon


2 Jan 1945. Contract Change Notification No. R. (259) 1. The following contract change in reference to procuring parts for and constructing 3- and 4-cylinder test engines is approved:

Contractor shall be permitted to procure parts for and construct:

[RG342 RD2311 XR-7755 Contract W-33-038AC-564 Supp Agreements, CCNs, COs. 450102012.]

6 Feb 1945. Supplemental Agreement No. 1 (S-8279) to Contract No. W 33-038 ac-564 (11169), a Cost-Plus-A-Fixed-Fee Contract for Supplies, was modified and supplemented as follows:

First: Article 3 of the Supplies contract is amended by adding to paragraph (b) the following subparagraph:

"(4) The cost to the Contractor of tools, dies, jigs, patterns and fixtures required for the performance of this contract and for which Contractor is not reimbursed otherwise than under this contract, but not including any items of capital equipment furnished by Defense Plant corporation or otherwise, shall be an allowable item of cost hereunder and title to all such property shall best in the Government in accordance with the provisions of article 22 hereof."

Second: Except as hereby modified, either expressly or by necessary implication, all the terms, covenants and conditions of the Supplies Contract shall continue in full force and effect.

Third: This Supplemental Agreement shall be subject to the written approval of the Secretary of War or such individual as said Secretary may designate and shall not be binding until so approved. [RG342 RD2311 XR-7755 Contract W-33-038AC-564 Supp Agreements, CCNs, COs. 450206010.]

14 Feb 1945. Following up on a 24 Jan 1945 letter from Lycoming, Blackwood forwarded Acting PPL Chief Col D.J. Keirn's approval to conduct the following test under paragraph No. 14 of Item No. 12-4 of Exhibit 1 to subject contract:

Lycoming's request to substitute short-stroke XR-7755 single-cylinder engine testing in lieu of further X-2 engine testing under Item No. 12-3 of Exhibit 1 to subject contract is being initiated. A Change Order covering such approval should be received by Lycoming in the near future. [RG 342 RD 2311 XR-7755 Contract W-33-038AC-564 Authorizing Correspondence. 004.]

24 Feb 1945. Col Keirn wrote Lycoming regarding Development of Synthetic Rubber Parts to Withstand Xylidine.

In a 5 Mar 1945 conference with Blackwood, Lycoming objected that the tests specified in Paragraph 8 were not easily accomplished on the single-cylinder specified in Item 12-4, and suggested that such tests be confined to the Materials Laboratory until a multi-cylinder XR-7755 was available. They might be accomplished by submerging samples of the various rubber-like materials for periods of time in the specified fuels and oils and inspecting for deterioration and swelling. [RG 342 RD 2311 XR-7755 Contract W-33-038AC-564 Authorizing Correspondence. 005-006.]

24 Feb 1945. Supplemental Agreement No. 1 (S-8279), approved 24 Feb 1945 and based on a 14 Nov 1944 IOM for Allowable Items of Cost. {The remainder is missing} [RG342 RD2311 XR-7755 Contract W-33-038AC-564 Supp Agreements, CCNs, COs. 440224009.]

28 Feb 1945. Supplemental Agreement No. 3 (S-10320) to Contract W 33-038 ac-564.

Preliminary negotiations between Lycoming and the Government assumed that the development Lycoming furnish would be on a fixed-price basis and resulted in the Letter Contract dated 24 Aug 1943. This Letter Contract was superseded by a Cost-Plus-Fixed-Fee (CPFF) Supplies Contract, dated 12 Aug 1944 and approved 18 Aug 1944. Article 3 paragraph (b) subparagraph (1) of this Supplies Contract recognized that prior to 1 Aug 1944 Lycoming maintained records of its expenditures under the Letter Contract "in accordance with its regular methods of conducting business under fixed-price contracts" and placed orders on an "advise-price" basis, and provided that all Letter Contract costs incurred by Lycoming were allowable items of cost. Lycoming was unable to change its accounting system to a CPFF basis until 1 Sep 1944. Lycoming provided a statement of its Letter Contract costs from 27 Jul 1943 through 31 Aug 1944, amounting to the sum of $759,192.44; the AAF Resident Auditor at Lycoming's Plant audited and approved this cost statement and determined that the $759,192.44 sum constituted proper reimbursement for all costs incurred by Lycoming up to 1 Sep 1944. In order to save the labor, time, and expense involved in Lycoming restating all such costs in proper CPFF form, and in re-auditing these costs, Lycoming and the Government agreed that Lycoming costs pursuant to the Letter Contract dated 24 Aug 1943 and under or in anticipation of the Supplies Contract up to and including 31 Aug 1944, Lycoming was entitled to reimbursement of $759,192.44 for all costs it incurred pursuant to the Letter Contract dated 24 Aug 1943 and under or in anticipation of the Supplies Contract up to and including 31 Aug 1944 and in complete satisfaction and discharge of all its right to reimbursement for costs under the provisions of Supply Contract Article 3 paragraph (b) subparagraph (1). Lycoming warranted that it had not submitting any claim, and would not in the future submit any claim for services or costs incurred prior to 1 Sep 1944. [RG 342 RD2311. XR-7755 Contract W-33-038AC-564. Supplement Agreements, CCNs, COs. 450228016-020]

13 Mar 1945. Lycomings B.J. Ryder wrote MatCmd's L.D. Bevan recommending exemptions to several specification paragraphs so that X-7 development could proceed more expeditiously:
1. AN-9502c – Engine, Qualification Test for Aircraft Reciprocating (Superseded by MIL-E-25111)
AN-9503c - Engines, Acceptance Test for Aircraft Reciprocating (Superseded by MIL-E-25112)

[RG342 RD2311. XR-7755, EO 503-602 Procurement, 1945 after Exhibit 3, AFP # 421265, EO 503-602. 450313042-043.]

26 Mar 1945. Following up on an 8 Mar 1945 Lycoming letter regarding Special Tests on Gaskets and Rubber-Like Materials Exposed to Fuels, Col D.J. Keirn elucidated an ATSC letter of 24 Feb 1945, which was intended to present the overall problems and requirements, and to indicate the only existing contract item under which it appeared tests of a very preliminary nature might be obtained on the single-cylinder engine hoses and gaskets. However, since those engines would be obligated to more extensive testing during XR-7755 engine development, such testing will be very limited. In view of this situation, Lycoming's suggestion that those tests be confined to the laboratory was at that time satisfactory. Col Keirn pointed out that no list of materials approved for use with these special fuels was available and suggested that materials presently used were to be checked with these fuels. [RG 342 RD 2311 XR-7755 Contract W-33-038AC-564 Authorizing Correspondence. 005.]

28 Apr 1945. Supplemental Agreement No. 4. (S-11414) to Contract W 33-038 ac-564 (11169)

First: Exhibit 1 to Item 12 of the Supplies Contract  is hereby amended as follows:
Second: Article 1 of the Supplies Contract is hereby amended as follows:

Third, Forth, Fifth: Contractual Boilerplate [RG 342 RD2311. XR-7755 Contract W-33-038AC-564. Supplement Agreements, CCNs, Change Orders. 450428021-026.]

6 Jun 1945. Lycoming's C.H. Wiegman was working with MatCmd's L.D. Bevan to define Contract W-33-038 ac-564 scope of work from 1 Sep 1945 to 1 Sep 1946. This was based on communication from MatCmd to Wiegman on 28 and 28 May 1945, as well as the call items agreed upon by Blackwood and Hoffman on 14 Jul 1944. On 6 Jun 1945, Wiegman wrote a draft proposal letter to MatCmd's L.D. Bevan detailing contract items that were to be accomplished over the next year. Bevan returned the letter to Wiegman after penciling in corrections, additions and suggestions. [RG342 RD2311 XR-7755. 503-602 Procurement. 450606035-041.]

7 Jul 1945. Lycoming's R.E. Posthauer replied with an expanded version of the 6 Jun 1945 Wiegman letter proposal. It was again marked up and returned. [RG342 RD2311 XR-7755. 503-602 Procurement. 450606035-041.]

20 Jul 1945. Blackwood was preparing an Authority for Purchase request that would be dated 3 Aug 1945 and assigned AFP No. 421265. This Contract W-33-038 ac-564 amendment covered further XR-7755 development. The AFP request providing a brief project background, justifications for the project's continuance, and explained its importance to future large bombers. The AFP request included exhibits explaining the work to be accomplished under the AFP, some of which amended previous contract items and other new items.

Although Blackwood's paperwork was dated 20 Jul 1945 and 2 Aug 1945, it was based on a 27 Aug 1945 proposal letter from Lycoming's Military Contracts & Service Manager, R.E. Posthauer. The proposal letter was at times different from Blackwood's AFP request. It also used different item numbering. For this reason, the Items below will show both the Lycoming and AFP Item numbering and narrative.

(1) Lycoming Item 12-15 (AFP Item 13)
Proposal
: Assembly, necessary redesign, test work, redesigned parts and test equipment required for 500 hrs testing necessary to accomplish a 50-hr nose-to-nose endurance test of the two reduction gear units furnished under Contract item 12-10, and a shifting test. The test conditions shall be established by mutual agreement between the Contractor and PPL. Three test report copies shall be furnished. Delivery = 1 Apr 1946; Estimated Cost = $100,464.00.

(2) Lycoming Item 12-17 (Contract Item 12-4, Continuation of Item 12-2)
Proposal
: Necessary design and test work and parts required for 2,500 hrs of single-, three- or four-cylinder engine testing as provided in Contract Article 1 Paragraph (f) for endurance test of Lycoming XR-7755-1 cylinder. This item shall cover tests of revised and/or improved designs. At least 500 hrs shall be at or above takeoff power and speed; 500 hrs at or above normal power and speed; 500 hrs at best economy cruising conditions; the remainder at or above minimum cruising; all ratings shall be as defined in Contract Item 12-5.
Contract Item 12-4 (amended): Necessary redesign, parts and testing required for 2,500 hrs additional performance and calibration testing of 1-, 3- and 4-cylinder engines as a continuation of the work called for under Contract Exhibit 1 Item 12-4 and as provided by Contract Article 1 Paragraph (f). At least 250 hrs shall be run at or above normal power and speed; the remainder shall be at or above minimum cruising; all ratings shall be as defined in Contract Exhibit 1 Item 12-5. Three test report copies shall be furnished. Delivery = 1 Sep 1946; Estimated Cost = $184,575.00.

(3) Lycoming Item 12-16 (Contract Item 12-2, Continuation of Item 12-4)
Proposal
: Necessary design, test work and parts required for 2,500 hrs XR-7755-1 single-, three- or four-cylinder engine testing as provided in Contract Article 1 Paragraph (f) for performance and calibration testing of the original, revised and/or improved designs. At least 250 hrs at or above normal power and speed; the remainder at or above minimum cruising; all ratings shall be as defined in Contract Item 12-5. These tests shall include the following:

Three report copies shall be provided. Delivery = 1 Sep 1946; Cost = $184.575.00

(4) Lycoming Item 12-18 (AFP Item 14)
Proposal
: Necessary redesign and test work and parts required for 400 hrs testing to include a 50-hr development test of an XR-7755-1 or XR-7755-5 engine built under Call 2 Item 12-11. A propeller suitable for running these tests shall be furnished by the Government. The 50-hr development test shall be run at conditions specified in Air Corps Specification No. 28144-A except that supercharger tests under Paragraph F-6c and such other conditions as may be agreed upon between the Contractor and PPL shall be deleted. Three report copies shall be furnished. Delivery = 30 Aug 1946; Estimated Cost = $282,877.00.

(5) Lycoming Item 12-19 (AFP Item 15)
Proposal
: Build one XR-7755-3 engine meeting the requirements of Lycoming Specification No. 2031 dated 4 Jun 1945, with such modifications thereto as the Contractor and PPL may agree upon using parts of Contract Items 12-8 and 12-10.

Necessary redesign parts and testing required for 100 hrs testing to include a 50-hr development test of same. Suitable propellers for running these tests shall be furnished by the Government. The test shall be conducted in accordance with the following schedule:
AFP Item 15 (new): Build one XR-7755-3 engine meeting the requirements of Lycoming Specification No. 2031-A, dated 4 Jun 1945, with such modifications thereto as the Contractor and PPL may agree upon, using the parts if Exhibit 1 Item 12-8, and one of the reduction gear units assembled under Exhibit 1 Item 1. Also provide necessary redesign, parts and testing required for 100 hrs testing to include a 50-hr development test of this XR-7755-3 engine without major failure or other major unsatisfactory conditions if testing time permits. Suitable propellers for running such tests shall be furnished by the Government. The test shall be conducted in accordance with the following schedule: The remainder of the test hours of this item, if any, shall be conducted in a manner agreed upon between the Contractor and PPL at the time of testing. Three test report copies shall be furnished. Delivery = 31 Aug 1945; estimated cost = $70,720.00.
(6) Lycoming Item 12-20 (AFP Item 16)
Proposal
: Necessary redesign, parts and testing required for 100 hrs performance testing accomplished on an XR-7755-1 or XR-7755-5 multicylinder engine built under Call 2 Item 12-11. Insofar as the testing time permits, these tests shall include the following: Three test report copies shall be furnished. Delivery = 18 Jul 1946; estimated cost = $70,720.00.

[RG342 RD2311 XR-7755. 503-602 Procurement. 450827015-018.]

AFP Notes:
AFP No. 421265 General Remarks [RG 342 RD2311. XR-7755\XR-7755 Contract W-33-038AC-564, Contract Calls. 450720001-005, 450720127.]

 

June – August 1945. While Lycoming and the ATSC Contracts branch worked through the Contract W-33-038 ac-564 FY 1946 (1 Sep 1945 – 1 Sep 1946) Scope of Work, Blackwood was busy with an Authority for Purchase (AFP) and an Expenditure Order (EO) Amendment that would continue funding XR-7755 development work in the austere post-V-J-Day economic environment. The AFP would encumber the funds while the EO would disburse them. Both required sole-source justifications, which would award the work to Lycoming on a non-competitive basis since only Lycoming was capable of completing the engine development.

Blackwood had determined that only $900,000.00 was available for FY 1946 activities, and had been coaching Lycoming to help keep its FY 1946 proposal in line with available funds. In some cases, this involved a reduction in the hours that had been originally budgeted and possibly an extension of tasks into future fiscal years; in other cases, Lycoming reduced its cost to cover the same deliverable Item. Blackwood suggested that Lycoming plan to perform whatever multi-cylinder running that could reasonably be accomplished, then spend the remainder of the money on one-, three- and four-cylinder running. He did not want to jeopardize any possible multi running. Blackwood was also keeping his upper management informed of the negotiations, as one of them would have to sign off on the final agreement. [RG342 RD2311. XR-7755, EO 503-602 Procurement, 1945 after Exhibit 3, AFP # 421265, EO 503-602. 450803007-014.]

 

10 Aug 1945. Blackwood released two contract calls to Contract W-33-038 ac-564, both originated 11 May 1945. Exhibit 2 Call 2, consisting of 2 Call Items to Contract Item 12, was approved on 21 Sep 1945 by Air Corps Contracting Officer 1st Lt Robert B. Thomas.

Call 2 Item 12-11. Build one XR-7755-1 engine using one part set call for by Item 12-8 and build one XR-7755-5 engine in accordance with Lycoming Model Specification No. 2030 dated 10 Apr 1945, with such modifications thereto as Contractor and PPL may agree upon. Such XR-7755-5 engine shall be built using one part set called for by Item 12-8 and using fuel injection pumps and equipment of Items 10 and 11. Also, accomplish necessary design, provide necessary parts and accomplish the necessary testing required for a maximum of 300 hrs testing on the engines built herein. Such testing shall include calibrations; performance checks; manifolding, torsional vibration, spark advance, valve timing, supercharger and fuel injection investigations; and coolant, oil and heat rejection tests that are to be accomplished prior to the acceptance tests of these two engines. Three test report copies shall be furnished. Delivery = 15 Dec 1945; estimated cost = $175,780.00.

Call 2 Item 12-12. Necessary design, parts and testing required for 150 hrs acceptance testing on engines called for by Exhibit 1 Item 1 and in accordance with Specification AN-9503c with exceptions that may be necessary and agreed upon between the Contractor and the Government at the time of testing. Three test report copies shall be furnished. Delivery = 15 Feb 1946; estimated cost = $68,697.00. [RG 342 RD2311. XR-7755\XR-7755 Contract W-33-038AC-564, Contract Calls. 014-015.]

10 Aug 1945. Blackwood released Exhibit 3 Call 3 to Contract W-33-038 ac-564 originated 21 Jul 1945. It was approved on 1 Oct 1945 by Air Corps Contracting Officer 1st Lt Robert B. Thomas.

Call 3 Item 12-13. 500 hrs additional testing under the conditions of Exhibit 1 Item 12-4, as amended, and three test report copies. Delivery = 1 Nov 1945; estimated cost = $35,890.00. [RG 342 RD2311. XR-7755\XR-7755 Contract W-33-038AC-564, Contract Calls. 016]

10 Sep 1945. Blackwood released Exhibit 4 Call 4 to Contract W-33-038 ac-564 originated 18 Aug 1945. It was approved on 1 Oct 1945 by Air Corps Contracting Officer 1st Lt Robert B. Thomas.

Call 4 Item 12-14. Additional 500 hrs testing under the conditions of Contract Exhibit 1 Item 12-2, as amended, but excluding short-stroke running. At least 100 hrs shall be at or above takeoff power and speed; 100 hrs at or above normal power and speed; 100 hrs at best economy cruising conditions; the remainder at or above minimum cruising conditions; all ratings shall be as defined in Contract Exhibit 1 Item 12-5. Three test report copies shall be furnished. Delivery = 1 Feb 1946; estimated cost = $35,890.00. [RG 342 RD2311. XR-7755\XR-7755 Contract W-33-038AC-564, Contract Calls. 017.]

5 Nov 1945. Blackwood released Exhibit 5 Call 5 to Contract W-33-038 ac-564 originated 11 Oct 1945. It was approved by Air Corps Contracting Officer 1st Lt Robert B. Thomas. Call 5 Item 12-15. Additional 200 hrs testing under conditions of Exhibit 1 Item 12-4, as amended. Three test report copies shall be furnished. Delivery = 1 Feb 1946; estimated cost = $14,357.00. [RG 342 RD2311. XR-7755\XR-7755 Contract W-33-038AC-564, Contract Calls. 018.]

18 Aug 1945. On 15 Aug 1945, Radio Tokyo broadcast a recorded message from Japanese Emperor Hirohito to the Japanese people announcing the surrender of the Empire of Japan, thus ending WWII. The U.S. Government almost immediately began shutting down most of the massive defense industry. On 18 Aug 1945, Blackwood received word from Joseph F. Heavey, the Philadelphia-based Director of Engineering for the Defense Plant Corporation (DPC) that all XR-7755 work was to stop immediately. The DPC, a subsidiary of the Reconstruction Finance Corporation (RFC), financed most new factories created to provide war materiel by financially supporting state and local governments, banks, railroads, mortgage associations, and other businesses supporting the war effort; it had provided partial funding for Lycoming's new test facility under Plancor 2212. The RFC, founded in 1932, was a government-sponsored financial institution that provided financial aid during the Great Depression and WWII. Plancor was a contraction of Plant Corporation, a designation used by the RFC to administer wartime plants. As many as 2,511 DPC Plancor facilities, designated Plancor 1 through 2511, were built.

Blackwood immediately set to work writing justifications for continuing XR-7755 work, and in particular, continuing test facility construction. He called Posthauer at Lycoming and requested detailed accounting of what was still to be completed and how much it would cost. In the mean time, Blackwood created a Routing and Record sheet on 20 Aug 1945 detailing that Plancor had allocated $983,000.00, $900,000.00 of which was committed. The large dynamometer was expected to cost $74,000.00, with an initial payment of $30,000.00. At that time the test facility building was structurally complete with electrical and plumbing work ongoing. Equipment installation was expected to commence in two weeks. [Penciled notes by J.G. Blackwood. RG 342 RD2311 XR-7755, 1943-1948: 503-602 Conf and Tel Notes. 450818151-152.]

31 Aug 1945. Completing the MX-434 AFP (which would be assigned AFP No. 421265) involved filling out the appropriate forms, and including an Exhibit that essentially mirrored the Contract Scope of Work. In addition, the AFP noted that synthetic rubber was required, controlled materials were involved, the estimated materials cost was unknown, the XR-7755 was not on the AAF Stock List, and that Lycoming license rights were to be considered. In the AFP Form's General Remarks section, Blackwood provided the following Scope of Work Summary: [RG342 RD2311. XR-7755, EO 503-602 Procurement, 1945 after Exhibit 3, AFP # 421265, EO 503-602. 450831002-004, 450831024-029.]

 

30 Oct 1945. Lycoming Chief Engineer C.H. Wiegman wrote the ATSC explaining engine run-time discrepancies between Lycoming progress reports and AAF representative's reports.

(1) All test reports and data sheets had been reviewed, which resulted in the following:

ItemReported
Time (hrs)
Correct
Time (hrs)
1890.9976.2
21,342.42,271.6
3765.9773.6
12-1122.2122.3
12-22,000.01,998.7
12-3563.5562.9
12-41,000.0920.1
12-50.00.0
12-13 50.2
12-14 191.8*
* As of 15 Oct 1945

 

(2) Causes for the discrepancies were varied:

(3) Because the corrected total time for Item 12-4 is less than the 1,000 hrs called for n the contract, it is requested that the Contractor be granted permission to reopen this Item and run the remaining test 79.9 hrs. This added time will in no way affect the original cost estimate.

(4) In paragraph 1(a) of the 1 Aug 1945 Lycoming letter, request was made to modify the contract to permit 765.9 testing hours under Item 3 instead of the authorized 600 hrs. Because of the corrected total time shown above, it is requested that the contract be modified to permit 773.6 testing hrs under Item 3 instead of the amount requested in the 1 August letter.

(5) In paragraph 1(c) of Lycoming's 1 Aug 1945 letter, a similar request was made regarding Item 12-3. Because of the revision of figures it is requested that 562.4 hrs testing hours be permitted under Item 12-3 instead of the amount requested in the 1 Aug 1945 letter.

On 15 Nov 1945, PPL Chief Col D.J. Keirn wrote Lycoming concurring with Lycoming's plan to run the remaining 79.9 test hours authorized by Item 12-4 with no cost change from the original estimate. Regarding paragraphs 4 and 5, a no-cost contract change order had been initiated to modify the test hours. [RG 342 RD 2311 XR-7755 Contract W-33-038AC-564 Authorizing Correspondence. 009-011.]

12 Nov 1945. Col D.J. Keirn, PPL Chief, proposed a no-cost Change Order to Contract W-33-038 ac-654, following up on a Routing and Record Sheet originated by Blackwood on 3 Aug 1945 and a Lycoming letter dated 1 Aug 1945.
  1. In Contract Item 3, the words "600 hrs" were to be amended to read "773.6 hrs."
  2. In Exhibit 1 Item 12-2 the words "a maximum of 25% of this time" was to be amended to read "a maximum of 592 hrs of this time."
  3. In Exhibit 1 Item 12-3 the quantity "500 hrs" in two places was to be amended to read "562.9 hrs."

These changes were requested because the extra running accomplished was necessary in single-cylinder development and Lycoming stated that the cost incurred in this extra running has not exceeded the original hours estimate. [RG 342 RD2311. XR-7755\XR-7755 Contract W-33-038AC-564, Contract Calls. 451112033.]

26 Nov 1945. Supplemental Agreement No. 5 to Contract W 33-038 ac-564. Approved 14 Dec 1945. (Note: The file contained two copies of this document, one of which had margin annotations that were apparently completion dates. I shall identify the annotations {by enclosing them in curly braces}.

(1) Item 12-2, is supplemented as follows: {Feb 1947}
Necessary redesign, parts and testing required for 2,500 hours of additional endurance testing or one-, three- or four-cylinder engines as a continuation of the work called for under Item 12-2, but excluding short-stroke running and the option contained in paragraph (f). At least 500 hours shall be at or above takeoff power and speed; 500 hours shall be at or above normal power and speed; 500 hours at best economy cruising conditions; the remaining 1,000 hours shall be at or above minimum cruising. All ratings related to such testing shall b e defined in Item 12-5 of this contract. Three report copies were to be furnished.

(2) Item 12-4 is supplemented as follows: {Apr 1947}
Necessary redesign, parts, and testing required for 2,500 hours of additional performance and calibration testing of one-, three- or four-cylinder engines as a continuation of the work called for under Item 12-4 of this contract. At least 250 hours shall be run at or above normal power and speed; the remaining 2,250 hours shall be at or above minimum cruising. All ratings related to such testing shall be as defined in Item 12-5 of this contract. Three report copies were to be furnished.

(3) Item 13 – Necessary redesign, parts, assembly and 500 hours of testing required to accomplish a 50-hr nose-to-nose endurance test of the two Government loaned reduction gear units manufactured under Item 12-10 of this contract, and a shifting test, without a major failure or other unsatisfactory condition. The conditions of such tests shall be established by mutual agreement between Lycoming and the PPL prior to the start of actual running. Three report copies were to be furnished. {Units in Oct 1946; endurance test 10 Dec 1946}

(4) Item 14 – Necessary redesign, parts and 500 hours testing to include a satisfactory 50-hr development test on an XR-7755-1 or XR-7755-5 engine built under Item 12-11. Such development test shall be conducted in accordance with Army Air Corps Specification No. 28144-A, dated 25 Aug 1939, with the exception that the requirements of Paragraph F-6c thereof shall be omitted and any other omissions and/or exceptions as may be necessary providing such omissions and/or exceptions have been agreed upon between Lycoming and the Government at the time of testing. A propeller suitable for use during the running of these tests shall be loaned by the Government. Three report copies were to be furnished. {Apr 1947}

(5) Item 15 – Build one XR-7755-3 engine in accordance with the requirements of Lycoming Specification No 2031-A dated 4 Jun 1945, with such modifications thereto as may be agreed upon between Lycoming and the PPL, using parts produced under Item 12-8 and one reduction gear unit assembled under Item 13, hereof. Provide the necessary redesign, parts and 100 hours of testing to include a 50-hr development test on the XR-7755-3 engine built under this item, without major failure or other unsatisfactory conditions if the testing time permits. Such test shall be conducted in accordance with the following schedule: Any remaining test hours of this item shall be conducted in a manner agreed upon between Lycoming and PPL Chief prior to running the hours. Suitable propellers for running the aforementioned tests shall be loaned by the Government. Three report copies were to be furnished. {4 months after #3, Item 13 (estimated Mar 1947)}

 

(6) Item 16 – Necessary redesign, parts and testing required for 100 hours performance testing on an XR-7755-1, XR-7755-3 or XR-7755-5 engine built under Item 12-11 or Item 15 of this contract. Insofar as the testing time permits tests shall include the following:

(7) Special Provisions = contractual boilerplate.

(8) Loan of Government Property = contractual boilerplate.

[RG 342 RD2311. XR-7755 Contract W-33-038AC-564. Supplement Agreements, CCNs, Change Orders. 451126046-052.]