The Lycoming XR-7755
Contracts/Administrative Chronology, 1946
by Kimble D. McCutcheon

9 Jun 1946. Supplemental Agreement No. 7 (S-16919) to Supplies Contract No. W 33-038 ac-564 (11169); AFP 421265; Contractor – The Aviation Corporation (Lycoming Division); Supplemental Agreement For: Additional Development Work
Change in Estimated Cost: Increase = $859,549.04; Change in Fixed Fee: Increase = $34,381.96

The parties agree as follows:

First: Item 12 Exhibit 1 is amended as follows:

(a) In addition to the work called for under Item 12-2, Lycoming shall perform the following:

Necessary redesign, parts and testing required for 2,500 hrs of additional endurance testing of one-, three- or four-cylinder engines as a continuation of the work called for under Item 12-2, Exhibit 1 to Item 12, but excluding short-stroke running and the option contained in paragraph (f) of Article 1 of the Supplies Contract. At least 500 hrs shall be at or above takeoff power and speed; 500 hrs at best economy cruising conditions; the remaining 1,000 hrs shall be at or above minimum cruising. All ratings related to such testing shall be as defined in Item 12-5 of the supplies contract. Three report copies were to be furnished.

(b) In addition to the work called under Item 12-4, Lycoming shall perform the following:

Necessary redesign, parts and testing required for 2,500 hrs of additional performance and calibration testing of one-, three- and four-cylinder engines a continuance of the work called for under Item 12-4. At least 250 hrs shall be run at or above normal power and speed; the remaining 2,250 hrs shall be at or above minimum cruising. All ratings related to such testing shall be as defined in Item 12-5. Three report copies were to be furnished.

Second: Supply Contract Statement of Work Article 1 is amended as follows:

(a) By adding after Item 12 of paragraph (a) thereof the following new items:

Item 13 – Necessary redesign, parts, assembly and 500 hrs 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, and a shifting test without a major failure or other major unsatisfactory condition of any of the reduction gear components. The conditions of such tests shall be established by mutual agreement between Lycoming and the PPL. Three report copies were to be furnished.

Item 14 – Necessary redesign, parts and 400 hrs of testing to include a satisfactory 50-r 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 b necessary providing such omissions and/or exceptions have been agreed upon between Lycoming and the Government. After successfully completing the 50-hr test, the remainder of the test hours of this item, if any, shall be conducted in a manner agreed upon between Lycoming an the PPL Chief. A propeller suitable for use during the running of these tests shall be loaned by the Government. Three report copies were to be furnished.

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 Chief, using the parts produced under Item 12-8 and one reduction gear unit assembled under Item 13. Provide the necessary redesign, parts and testing required for 100 hrs testing to include a 50-hr development test on the XR-7755-3 without a major failure or other major unsatisfactory condition if the testing time permits. Such test shall be conducted according to the following schedule:
  1. Five hours at approximately 1,300 rpm and 89 bmep with 0.354 reduction gear ratio and best economy fuel-air ratio.
  2. Five hours at approximately 1,600 rpm and 125 bmep with 0.354 reduction gear ratio and best economy fuel-air ratio.
  3. Ten hours at approximately 1,900 rpm and 135 bmep with 0.354 reduction gear ratio and best economy fuel-air ratio.
  4. Ten hours at approximately 2,200 rpm and 139 bmep with 0.246 reduction gear ratio and best economy fuel-air ratio.
  5. Ten hours at approximately 2,300 rpm and 178 bmep with 0.246 reduction gear ratio and best economy fuel-air ratio.
  6. Ten hours in accordance with a reduction gear ratio shift cycle as mutually agreed upon between Lycoming and the PPL Chief.
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.

 

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:
  1. Torsional vibration checks.
  2. Tests to determine optimum spark, valve and fuel injection timing
  3. Heat rejection to coolant and oil.
  4. Calibration.
  5. Air-fuel distribution investigation.
  6. Manifolding.
  7. Comparison of fuel injection versus carburetion.
  8. Supercharging.
  9. Spark plug performance.
  10. Other tests approved by the PPL.
Three report copies were to be furnished.

 

(b) By adding after paragraph (g) thereof the following new paragraph:
Third: Article 2 – Estimated Costs of the Supplies Contract is amended and supplemented as follows:

Forth: Article 3 – Consideration – of the Supplies Contract is amended and supplemented as follows:

(a) By deleting the first sentence of paragraph (a) subparagraph (1) thereof and by substituting therefore the following:

"(1) In addition the Government will pay the Contractor for work performed pursuant to Item 12 of Article 1(a) hereof a fixed fee of four per cent (4%) of the estimated cost st forth in all Exhibits approved and attached hereto and made a part hereof as provided in said Item 12 and as said Exhibits may be amended by Supplemental Agreement or Change Orders hereto. Further, that Government will pay the Contractor for work performed pursuant to Items 13 to 16 inclusive of Article 1(a) hereof a fixed fee of Twenty Thousand One Hundred Eighty Three Dollars and Eighty-Eight Cents ($20,183.88)(being 4% of the estimated cost of Five Hundred Four Thousand Five Hundred Ninety-Seven Dollars and Twelve Cents ($504,597.12) for said Items 13 to 16 inclusive)."

(b) By adding a new subparagraph (5) to paragraph (b) thereof:

"(5) Costs of overtime wage payments subsequent to 1 Sep 1945, shall be allowable at lower of the costs hereunder only as and to the extent that the overtime work for which payments are made shall have been expressly authorized in writing by the Contracting Officer propr to the performance of such work."

Fifth: Article 4 – Delivery – of the Supplies Contract is amended and supplemented as follows:

Sixth: Article 6 of the Supplies Contract is hereby amended by increasing the total sum allotted for this contract, referred to in paragraph (c) of said Article, by Eight Hundred Ninety-Three Thousand Nine Hundred Thirty-One Dollars ($893,931.00).

Seventh: This Supplemental Agreement in the formal contract contemplated by Supplement to Letter Contract addressed by the War Department to the Contractor under date of 26 Nov 1945, and this Supplemental Agreement, this Supplemental Agreement shall govern.

Eighth: The provisions of the Vinson-Trammel Act (which placed limits on profits for war materiel) for the following reasons:

Ninth: Nothing herein contained shall be deemed to require the Contractor to manufacture, furnish or deliver any articles or supplies, or to perform any work, as to which a Notice of Termination is in effect at the effective date hereof, nor to require the Government to accept any such articles, supplies or work; and any such new Notice of Termination shall be applicable, to the extent stated therein, to any articles, supplies or work calling for hereby or otherwise referred to herein.

Tenth: Except as hereby modified either expressly or by necessary implication all of the terms covenants and conditions of the Supplies Contract shall continue in full force and effect and shall apply to the articles and supplies to be furnished hereunder.

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

3 Sep 1946. R.E. Posthauer, Lycoming's Manager Military Contracts, wrote the ATSC requesting that Contract W 33-038 ac-564 Item 12-5 Change Order No. 8 to the Contract version dated 8 Aug 1946 be rewritten as follows:

A. Item 12-5, listed under Exhibit "1" to Item 12 as amended, is hereby revised as follows at no change in estimated cost and fixed fee:

17 Sep 1946. Power Plant Laboratory Chief Col R.J. Minty accepted Change Order No. 8 except that the last paragraph should have read, "…and future single cylinder tests specified under Items 1 and 2 of Supplement No. 7, approval now pending." [RG 342 RD 2311 XR-7755 Contract W-33-038AC-564 Authorizing Correspondence. 012-014.]

In the weeks prior to the 11 Sep 1946 conference between AMC and Lycoming at Wright Field, Blackwood, in a series of undated hand-written notes, appears to be preparing what would become Lycoming AFP 14587. This anticipated further contract calls prior to 30 Jun 1947 that would cover more turbine compounding development work, and included draft purchase request No. 14585, marked later cancelled. Also included was a working Exhibit A, scope of work to the above AFP, along with more hand-written preparatory notes and more draft AFP No. 14585 attachments. [RG 342 RD2311. XR-7755 Contract W-33-038 ac-564. Proposed Procurement and Mods. 001-005.]

The corresponding EO 503-602 Addendum 3 scope of work included: Estimated ATSC labor cost for this activity was previously estimated at $4,500.00; new estimate was $7,000.00. Previous estimate of Lycoming's work was $4,545,506.00; new estimate was $5,945,506.00. Total previous estimate was $4,550,006.00; new estimate was $5,952,506.00. Signed by Blackwood and Col Minty, PPL Chief.

 

At some point, PPL Chief Col Minty advised Blackwood, Chenoweth, and E.O. Wolfe that the project would be cancelled or restructured. The objective had switched to a 50-hr flight test and making an engine available for that test, which if successful, might result in the contract being reopened later. This led Blackwood to prepare undated contract status notes and tasks to be accomplished in connection with the contract cancellation/restructuring: [RG 342 RD2311. XR-7755 Contract W-33-038 ac-564. Proposed Procurement and Mods. 013-]

 

26 Sep 1946. R.E. Posthauer, Lycoming's Military Contracts Manager, wrote the PPL covering an 11 Sep 1946 conference at Wright Field, which had included Cols Minty, Wassel and O'Keefe, and Messrs. Berger and Blackwood; Posthauer and Carpenter had attended on behalf of Lycoming.

1. Lycoming produced a proposal in compliance with the conclusions reached.

2. The proposal consisted of the following items: Three report copies shall be submitted. Delivery = 26 months after contract; Cost = $588,420.00. Lycoming requested a 4% fee on all above items.
3. The subject of 4-cylinder testing was studied in some detail by the Contractor. The Contractor's conclusions were that it would be more advantageous and of more benefit to the Government to first accomplish the 1-cylinder testing as outlined in 2(c) above and then proceed with 4-cylinder testing if conditions indicated that this was necessary. The reasons for this are as follows:

4. Lycoming suggested, in view of the above that 4-cylinder work be put in the nature of a call to the subject contract. The contractor's proposal on this item is as follows: Necessary design, parts, tools, Jigs, fixtures, special instrumentation and testing to accomplish 300 hrs of endurance testing of a 4-cylinder in-line XR-7755 engine at condition based on information obtained from Items (a) and (c); these conditions to be agreed upon by the AMC and the Contractor. Three reports shall be submitted. Delivery = 12 months after contract; Cost = $172,530.00. [RG 342 RD2311. XR-7755 Contract W-33-038 ac-564. Proposed Procurement and Mods. 460926019-022]

23 Oct 1946. R.E. Posthaur, Lycoming's Military Contracts Manager, sent quotations to the AMC, responding to a verbal request: A fixed fee of 4% should be added to the above. [RG 342 RD2311. XR-7755 Contract W-33-038 ac-564. Proposed Procurement and Mods. 461023018.]

 

25 Oct 1946. Posthauer sent updated quotations, superseding those sent on 23 Oct 1946, with these revised quotes:
13 Nov 1946. Expenditure Order 503-602 Addendum 3, originated by Blackwood, was approved by PPL Chief Col R.J. Minty and Engineering Division Chief Maj Gen L.G. Craigie. This amended EO 503-602 to extend Call Contract W-533-038 ac-564 by $1,400,000.00 for the XR-7755 aircraft engine. Contract Calls were anticipated to cover the following:

27 Dec 1946. Blackwood produced a hand-written budget approximation after the project budget was cut from $1,400,000.00 to around $400,000.00.

ActivityCost
Single-Cylinder Performance Running$26,450.00
Studies$7,303.00
Single-Cylinder Endurance Running$37,134.00
XR-7755 Design, Layout and Modification$126,063.00
Design of Feedback Turbine,etc.$150,000.00
 ===========
Total$346,950.00

[RG 342 RD2311. XR-7755 Contract W-33-038 ac-564. Proposed Procurement and Mods. 461227023.]

 

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