The Lycoming XR-7755
Contracts/Administrative Chronology, 1943
by Kimble D. McCutcheon

Lycoming R-7755 Facilities

After termination of the Lycoming X-2470 program and after the lack of MatCmd interest in the Lycoming BX engine, MatCmd suggested that Lycoming consider developing a 5,000 hp engine, known variously as the X-5, X-6, X-7 and XR-7755.

17 Jun 1943. Lycoming submitted a list of machine tools and test equipment needed for X-5 Development.

[Penciled notes by J.G. Blackwood. RG 342 RD2311 XR-7755, 1943-1948: 503-602 Conf and Tel Notes. 430617059.]

17 Jul 1943. Lycoming submitted a final proposal for this project MX-434 and an Authority for Purchase (AFP) No. 381731 dated 14 Aug 1943 was initiated. The proposal listed required facilities to the extent of $713,469.75, which did not include buildings or land. Letter Contract W-33-038 ac-564, approved 15 Sep 1943 for the amount of $1,571,575.00, covered the first development phase. The letter contract was extended several times in the absence of a formal contract, which was held up over facilities and a disagreement of whether it would be a fixed-price or cost-plus. On 1 Nov 1943, Lycoming submitted a detailed Facilities Appendix in the amount of $1,209,516.00 (with a penciled revision to $1,218,334.00) through the Eastern Procurement District Supervisor, who forwarded it to the Wright Field Resource Control Section (RCS). On 12 Nov 1943, a conference between RCS, PPL and Lycoming [17 Nov 1943 Memorandum Report ENG 57-503-1060] made it clear that neither Defense Production Corporation (DPC) nor Emergency Plant Funds (EPF) money available to RCS could be used for these experimental facilities; Experimental Engineering funds would have to be used. Also, certain machine tools needed to be removed from the list and the list in general should be pared down to a bare minimum. Following up, on 16 Nov 1943, RCS sent an IOM to the PPL stating that Lycoming should negotiate with the PPL for Experimental Engineering funds. On 15 and 18 Nov 1943 [29 Nov 1944 Memorandum Report ENG 57-503-1073] a conference between Engineering Division and Lycoming made it clear that the difference between the original $713,469.65 facilities estimate and current $1,218,334.00 was due to Lycoming's inability to make up the difference from its production contract profits due to the Government having reduced the allowable margins. The X-6 facilities estimate alone was $985,000.00 and the remainder was for air-cooled engine programs that were not experimental status. It was concluded that the use of experimental funds for the X-6 engine alone would be acceptable except for the acquisition of new machine tools; Lycoming agreed to try locating used tools. On 26 Nov 1943, Lycoming wrote MatCmd submitting its recommended full program with $1,204,717.00 for facilities; an alternate proposal for $985,141.00 was submitted for X-6 facilities only . An IOM dated 7 Dec 1943 from PPL to RCS requested that RCS proceed with facilities arrangements on the basis of the X-6 engine only ($985,141.00) and indicated that the PPL had initiated an AFP to cover the transaction. However, in preparing the AFP Mr. Bierlein of the Budget Office questioned the legality of using Engineering Division funds for such purposes, especially for land and buildings. This was confirmed by Capt Pastner of Procurement. Telephone calls and a letter to Washington, DC, resulted in a teletype from Headquarters, Washington, DC Budget and Fiscal Office that Expediting Production Funds could be used for these facilities. An IOM dated 21 Dec 1943 superseding the 7 Dec IOM was sent to RCS requesting on the basis of permissible use of EPF that RCS furnish facilities. As a result of a conference between RCS and PPL, and an IOM to PPL dated 24 Dec 1943 the plan evolved to furnishing only the facilities needed for the single- and twin-cylinder engines and holding off on facilities involving buildings, big dynamometer, and tools for multi-cylinder development until completion of cylinder development. This plan was confirmed and approved by a 1st Indorsement dated 30 Dec 1943 to the 24 Dec IOM.

A 5 Jan 1944 Memorandum Report ENG 57-503-1115 covered a conference between the PPL and Lycoming where news of the curtailed development program (single-cylinder and multi-cylinder design) was conveyed, thereby curtailing the need for the full facilities amount. A special facilities contract was planned based on $985,000.00 with restrictions on buildings and time of large dynamometer delivery. This resulted in partial contract termination being proposed in an IOM dated 4 Jan 1944. However, a Lycoming memorandum dated 8 Jan 1944 to Gen Carroll detailed reasons why the program should not be restricted to single-cylinder work and why the program should proceed as originally proposed and contracted for. Gen Carroll accepted this and the 4 Jan IOM was returned with no action. At Gen Carroll's suggestion, an IOM dated 14 Jan 1944 was prepared by PPL to RCS superseding the 24 Dec 1943 IOM and 1st indorsement. The full original contract program was to be followed and test facilities were to be furnished in the amount of $985,000.00 without restriction.

Since the letter contract was initiated the engine design changed from the triple V-12 of the X-6 to the 4-row 9-cylinder-block radial X-7, RCS wanted a write-up justifying the utility of the single- and twin-cylinder dynamometers. However, Chenoweth after conversation with Gen Carroll stated that the facilities were being acted on and any new problems might delay the action and jeopardize the whole project. Since later adjustments could be made to realign dynamometer requirements to the X-7 program. The question again arose and although v-twin testing was no longer necessary, Lycoming stated that 1-, 3- and 4-cylinder should be tested to cover cylinder and block construction, valve mechanisms, and radial operating features. These three combinations should be tested on small dynamometers as cheaper and more rapid development would accrue. While these new requirements superseded the original requirements, it seemed that more or larger dynamometers would be appropriate. Exhibit A lists possible power requirements; Exhibit B gives personal reactions to teletype quotes. [Penciled notes by J.G. Blackwood. RG 342 RD2311 XR-7755, 1943-1948: 503-602 Conf and Tel Notes. 430717022-430717032.]

24 Aug 1943. Letter Contract W 33-038 ac-564 (11169) with The Aviation Corporation, Lycoming Division, Williamsport, Pennsylvania for services substantially in accordance with Exhibit B hereto attached and hereby made a part hereof, subject, however, to such changes therein and additions thereto as may be agreed upon between Lycoming and the Government. Total estimated price $1,571,575.00, with $471,472.50 expenditure approved (30% of total estimated cost). In the event a formal contract was not placed with Lycoming by 1 Oct 1943, then Lycoming had the right to demand letter contract termination by 1 Nov 1943. Lycoming also had the right to be reimbursed for all costs incurred and expenditures made. Authority for Purchase No. 381731. Allotment No. ACA 1942-44 2-4005 P 641-09 A 212/40705. Priority Rating AA-1. Equipment Class 02-A. Fixed Price.  Confidential Classification: Program MX434. Lycoming accepted this contract on 4 Sep 1943 and it was approved on 15 Sep 1943 by Col Alden R Crawford, Chief of Staff, Materiel Command.

Authority for Purchase 381731 Exhibit B

Item 2 1 ea report, in triplicate, covering single cylinder performance investigations accomplished during the first 12 months with liquid-cooled cylinders of a different size than those to be used on the Lycoming X-6 engine. The purpose of these investigations shall be to establish design criteria on compression ratio, valve timing, spark timing and similar characteristics related to the ultimate development of the Lycoming X-6 engine. The running accomplished in this item shall include a minimum of 50 hours of operation, at least 5 hours of which were to be at takeoff power and speed, 5 at normal power and speed, and the remainder at or above minimum cruising conditions.

Item 3 1 ea report, in triplicate, covering single cylinder endurance tests accomplished during the first 12 months on a cylinder of the same general design but a different size than the Lycoming X-6 engine. These tests These tests shall relate to the ultimate development of the Lycoming X-6 engine and shall include a minimum of 100 hrs of operation, at least 10 hrs of which shall be at takeoff power and speed, 10 hours at normal power and speed, and the remainder at or above minimum cruising conditions.

Item 4 1 set blueprints, in triplicate, of assembly and detail drawings covering the original design of the power section of the Lycoming X-6 engine meeting the requirements of Lycoming Specification No. 2020, dated 5 Jul 1943, having a nose in accordance with Type A of Lycoming Specification No. 2020, with a propeller reduction gear ratio of approximately 0.72:1, and an AN No. 60 propeller shaft end for dynamometer and propeller stand operation. Provision shall be made in the engine design to permit extension shaft operation with a reduction gear ratio substantially 1:1, as well as to permit installation of various types of propeller reduction gear drives as outlined in Lycoming Specification No. 2020.

Item 5 1 ea mockup engine of the Lycoming X-6 engine as described in Specification No. 2020.

Item 6 1 set parts, complete, required for one Lycoming X-6 engine meeting the requirements of Lycoming Specification No. 2020, dated 5 Jul 1943, hereby made a part hereof and subject to approval and release by the Commanding General, AAF Materiel Command, Wright Field or his duly authorized representative, prior to delivery of any engine on this contract to the Government. This engine shall have the Type A nose end provided in Lycoming Specification No. 2020, with a propeller reduction gear ratio of approximately 0.72:1 propeller and an AN No. 60 propeller shaft end.

Item 7 3 sets rough forgings, castings and bearings as required to make available for fabrication three complete engine parts sets as described in Item 6.

Item 8 1 ea report, in triplicate, covering Lycoming X-6 preliminary special development tests relating to the development of the Lycoming X-6 engine and accomplished with Lycoming X-6 and/or Lycoming BX engine parts during the first year to obtain design criteria on at least the following items: oil pressure pumps, oil scavenge pumps, valve gear surge and endurance characteristics, cylinder air flow and supercharger entry flow characteristics, connecting rod and piston strength, and main bearing capacity.

Item 9 1 ea report, in triplicate, covering miscellaneous tests relating to the development of the Lycoming X-6 and accomplished during the first year on multi-cylinder liquid-cooled engines other than the Lycoming X-6. The tests of this item shall cover at least the following: investigation of valve timing, fuel injection and distribution; and shall also cover endurance characteristics of the X-6 engine type of cylinder block construction. The tests of this item shall cover a minimum of 50 hrs operation.

Item 10 3 ea fuel injection pumps, 12 cylinder, complete with 36 nozzles. The design of this equipment shall be of the same design as that suitable for the Lycoming X-6 engine as described by Lycoming Specification No. 2020.

Item 11 1 set fuel injection equipment, complete, suitable for installation on a Lycoming X-6 engine meeting the requirements of Lycoming Specification No. 2020.

All tests shall be conducted at the Contractor's plant on fuel in accordance with Specification AN-F-28, Grade 130, dated 23 Dec 1942 and Amendment 1 dated 23 Mar 1943.

Fuel Injection. The Lycoming X-6 engine, meeting the requirements of Specification No. 2020, shall be designed for both fuel injection and carburetion, and full consideration shall be given in the design and development work on this contract to be the satisfactory development of said engine for fuel injection. Lycoming shall exert its best efforts toward delivering the Lycoming X-6 engine with fuel injection equipment.

Replacement of Parts. Parts which are of a design which would be used in a multi-cylinder engine meeting the requirements of Specification No. 2020 dated 4 Jul 1943, exclusive of parts of test equipment as such, which fail during the tests called for in Item 1 and in the Lycoming X-6 engine parts tests of Item 8 shall be replaced by the Contractor at the expense of the Government with like parts of the same or improved material or with redesigned parts of the same or improved material. Further, if inspection indicates that parts used in the aforementioned Items 1 and 8 which have not failed should be replaced, such parts shall be replaced at the expense of the Government with like parts of the same or improved material, or with redesigned pats of the same or improved material. Such parts shall be installed by and at the expense of the Contractor. The prices to be paid by the Government for any replacement of parts pursuant to the provisions of this Article shall include any redesign costs, if any, and shall be negotiated by the parties hereto at the time such replacement becomes necessary. A monthly statement shall be rendered as to the parts which are used in the testing and for which negotiations for Government payment shall be started. This statement shall be certified by the representative of the Procuring Agency. [RG342 RD2311 XR-7755 Contract W-33-038AC-564 Initial Letter Contract. 001-006.]

24 Sep 1943 through 22 Jul 1944. Contract W 33-038 ac-564 Amendment Nos. 1 through 9. Amendment No. 1 to the subject letter contract, dated 24 Aug 1943, accepted by Lycoming on 4 Sep 1943, and approved by the approving authority on 15 Sep 1943, provided that in the event the formal contract for the supplies referred to therein was not placed with you prior to 1 Oct 1943, the Government would, upon demand made prior to 1 Nov 1943 reimburse Lycoming for costs incurred, an assume obligations for commitments made in connection with the proposed procurement of said Supplies within the limit of $471,472.50, subject to the conditions therein stated. The Government opined that it would facilitate the prosecution of the war to extend the date of 1 Oct 1943, as set forth above, to 1 Dec 1943, and likewise extend the date of demand to 1 Jan 1944. The Aviation Corporation - Lycoming Division accepted this amendment on 1 Oct 1943. Amendments 2 through 9 were similarly worded except for the dated, which are summarized below. Note that amendments 3, 4, 7 and 8 do not appear in the file.

[RG 342 RD2311 XR-7755 Contract W-33-038AC-564. Initial Letter Contract. 007-012.]

15 and 18 Nov 1943. A conference at Materiel Center was attended by Heath, Johnson and Ryder of Lycoming, and Col Smith, Chenoweth and Blackwood of MatCmd. Lycoming was notified that the RCS had determined that the DPC would not furnish facilities moneys and that such moneys would have to come from Experimental Funds, which could not be used for facilities involving air-cooled engines, nor for the purchase of machinery restricted by the WPB. MatCmd advised Lycoming to drastically cut its facilities list and present a revised estimate to MatCmd. Lycoming countered that it did not wish to use its last parcel of land for the development of one project and therefore desired to have a unified building incorporating both air-cooled and liquid-cooled test provisions, a scheme that would result in a more efficient test organization.

The conference resumed at the PPL on 18 Nov after Lycoming had spoken with Aviation Corporation officials and estimated the cost of shipping out the machine work that would be necessary if machine tools costing $167,927.00 were not provided; the extra cost for gear work during the first year would be $136,500.00 and cause a two month delay. If the project took several years it would be cheaper to have the machine tools furnished, reduce delays, and result in higher-quality gears. Lycoming did not consider it feasible for the company to construct the required buildings on a company certificate of necessity.

Heath, Johnson and Ryder then met with Gen Carroll and presented a facilities discussion summary. The Lycoming facilities cost, including provisions for an air conditioned testing, was $1,218,334.00. This compares with $713,469.65 facilities cost as presented with the original X-6 proposal. The increase was due to Lycoming's inability to continue making up the difference from its own funds from existing production contracts. However, the production contracts had been reduced, as had the profit margins, and such funds were no longer available for covering engineering and development work.

Facilities cost for the X-6 alone was $985,000.00, of which the largest item was laboratory and test equipment amounting to $633,084.00, much of which was for a 5,000 hp dynamometer, twin dynamometer and engine component parts test equipment. Machine tools in the amount of $160,081.00 were also included.

Gen Carroll asked about the use of Lycoming's present XH-2470 engine equipment on this project, and Lycoming said it was being used where possible, but that since the X-6 power was double that of the XH-2470 the equipment was not of proper capacity. Lycoming reiterated that it was not in favor of building facilities only for the X-6, but instead favored a unified building since separate buildings would require separate utilities or numerous interconnections between new and present buildings that would be difficult to administer. Gen Carroll indicated that numerous facilities were becoming available and that experimental funds could be used for these. Since new tools were not available through the DPC, Gen Carroll thought Lycoming should submit a letter including a list of required tools so that MatCmd might locate tools that could be rented, bypassing the RCS and DPC objections. Lycoming was advised to revise its facilities proposal to cover only those facilities required for the X-6 engine project. [Penciled notes by J.G. Blackwood. RG 342 RD2311 XR-7755, 1943-1948: 503-602 Conf and Tel Notes. 431115047-431115053.]

23 Dec 1943. In an IOM addressed to the Power Plant Laboratory Chief, Prescott summarized the Lycoming facilities controversy. He had discussed Lycoming's views and attitudes with Maj Patch and Mr. Crowlitz. The amounts involved in buildings and facilities were approximately: Land – $7,345.00; Machine Tools – $166,000.00; Buildings – $264,000.00; Dynamometer and test equipment, including furniture and fixtures – $770,000.00; Total buildings and facilities – $1,209,000.00. Crowlitz stated that some of the machine tools were duplicated by by ones then in storage at Lycoming. He also stated that Lycoming would not finance any part of the test facilities or buildings.

Crowlitz suggested that the present outstanding EPF contracts, totaling $950,000.00, be paid off. Then the Government could take title, relieving Lycoming financially to that extent. He further suggested that the requested buildings and test equipment be built/acquired by the Government and sold back to Lycoming at a low interest rate amortized at 12.5% per year so the Government would be completely paid back in 8 years. The amounts for buildings and land would be amortized in 17 years, at which time the titles would go to Lycoming. During the time Government funds were tied up in the buildings and facilities, Crowlitz suggested that the Lycoming contract include a priority on Government investment in case of insolvency. In this case, the Government's investment would be made safe and at the same time the buildings and facilities would be available for Lycoming use at a low interest rate.

Crowlitz opined that a proposal of this nature would establish whether Lycoming was interested in proceeding with the development or merely equipping itself with these buildings and facilities to attain a good post-war position.

There had been discussion about Lycoming placing the building on a plot of ground adjacent to the present experimental laboratory so that steam, water and electricity could be easily furnished from the present facility. Maj Patch and Crowlitz felt that a proposal of this kind would clear the atmosphere, and if Lycoming was to proceed with the development program, the plan should be acceptable. Crowlitz felt that arrange would be a good one for the Government also. [Penciled notes by J.G. Blackwood. RG 342 RD2311 XR-7755, 1943-1948: 503-602 Conf and Tel Notes. 431223006 -431223007.]

24 or 25 Apr 1944. Maj Patch received a telephone call from Mr. Perkins of the War Production Board (WPD) in Washington, DC. Prescott got on the line and asked if the test facilities were in process; Perkins said yes, that Lycoming had been authorized to order dynamometers. Perkins added that the only hitch was two gear grinders, critical items needed in two other projects of immediate value to the war effort. Prescott suggested that a Lycoming representative familiar with the machine requirements contact Mr. Perkins and work out a delivery schedule that would delay neither the X-7 nor the other vital programs. Clearing this situation made way for formal contract preparation. At some point it had been proposed that one test facility be allocated for use by both Studebaker and Lycoming on a first come first serve basis; Studebaker had part of the test facility money under the Studebaker Contract No. W 535-ac-28386. [Penciled notes by J.G. Blackwood. RG 342 RD2311 XR-7755, 1943-1948: 503-602 Conf and Tel Notes. 430717002-430717003.]

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