Lycoming XR-7755 Contracts/Administrative, 1947

The Lycoming XR-7755
Contracts/Administrative Chronology, 1947
by Kimble D. McCutcheon

7 Jan 1947. Blackwood compiled an XR-7755 project status and revised program report for Col Minty. Contract items 2, 3, 4, 5, 6, 9, 12-1, 12-2 12-3, 12-4, 12-5 12-7 12-13, 12-14 and 12-15 were complete. A slight amount of work was approved for items 8 and 12-6. Items 10,11, 12-8, 12-10 and 12-11 were ongoing. Supplement 7, Item 4 was to be continued, except the 50-hr flight approval test IAW Specification XR-28398-A was to be used as a testing baseline. Items 1, 7, 12-9, 12-12, Work was to be stopped on Supplement No. 7 Items 1, 2, 3, 5 and 6.

Blackwood continued his exercise by estimating the cost of a revised XR-7755 program.

	Estimated Cost of Revised XR-7755 Program	Cost Based on Letter
Item 8	Letter now proposes to stop all tests on components except for problems on 50-hr test.	$50,000.00
Item 10	Continue
Item 11	Continue	$39,625.00
Item 12-6	Letter states stop all design unless mutually agreed on 50-hr test problem. Since current cost has been $3,100.00 per month, two years design would be $75,00.00. Cost is not high compared to crippling effect.
Item 12-8	Continue. Two engines are completed and one engine 70% complete. Estimated cost = 270 / 300 x $854,276.00	$85,428.00
Item 12-9	Letter stops item. In view of need of parts for test program this item is especially needed. Rough parts available and machining only is involved. Allowing 10% present completion, cost would be $187,000.00.
Item 12-10	Continue. Latest cost report might show a larger percent paid on this item and included in estimate of $3,246,00.00 cost as of 1 February as compared to approximately $130,800.00 unpaid on 1 December report, which gives $3,090,411.00 cost. It is believed an estimate of $120,000.00 is high if anything.	$120,000.00
Item 12-11	Continue	$137,600.00
Supp #7, Item 1	Letter stops all 1-, 3- and 4-cylinder testing. Suggest 1,500 total hours (700 already completed) be retained for endurance and performance to permit some investigation oof multi test problems.
Supp #7, Item 3	Letter stops item. Suggest testing be permitted to 200 hrs. This will permit any major defect determination and any additional development would have to be done as part of a multi engine.
Supp #7, Item 4	Continue. Apparently add hours to this item as accrued from reduction in program.	$282,877.00
	Total	$745,530.00
	Total amount obligated	$4,545,506.00
	Estimated total spent to 1 Feb 1947	$3,246,000.00
	Remaining funds	$1,300,000.00
Excess based on letter = $1,300,000.00 - $745,000.00 = $555,000.00
(Hourly cost of multi testing = $282,877.00 / 400 = $707.00 per hour)

[RG 342 RD 2311 XR-7755 Contract W-33-038AC-564 Proposed Procurement & Mods. 470107024, 470107029-030.]

7 Jan 1947. Blackwood prepared cost and status summaries:

Contract X-33-038 ac-564 Lycoming XR-7755 Work and Status Summary
Item	Work Called For	Estimated Cost	Actual Cost	Previous Status	Proposed Revised Status
1	Build four 1-, 3-, and 4-Cylinder engines; run performance tests.	$213,500.00	$187,346.66	Still building 4-cylinder.	Stop
2	1-cylinder performance tests on other engines	$56,000.00	$53,179.00	Complete	—
3	1-cylinder endurance tests on other engines	$40,000.00	$38,100.00	Complete	—
4	XR-7755-1 design, blueprints and design reports.	$260,000.00	$305,447.22	Complete	—
12-6	XR-7755-1 design (continuation of Item 4).	$158,582.00		Continuing	Continue on modified scale.
5	XR-7755-1 mock-up	$40,000.00	$36.749.05	Complete except for mods	Stop
6	Partially finished parts for three XR-7755-1.	$298,000.00		Complete	—
7	Three sets rough forgings, castings, bearings.	$75,000.00	$677,244.34	Continue	Stop except as authorized.
12-8	Completion of Item 6.	$854,276.00		Continue	Complete
12-9	One XR-7755-2 finished spare parts set.	$208,135.00		Continue	Stop
8	Special tests on components, etc.	$389,500.00	$413,066.03	Continue	Stop except for 50-hr test work.
9	Tests using X-2 and BX engines.	$150,000.00	$94,503.41	Complete	—
10	Three fuel injection pumps; 36 nozzles.	$18,825.00	$9,900.00	Continue	Continue
11	XR-7755-1 fuel injection equipment set.	$30,750.00		Continue	Continue
12-1	200 hrs on X-7 50-hr endurance test.	$15,431.00	$15,878.06	Complete	—
12-2	2,000 hrs X-7 endurance.	$154,326.00	$139,974.00	Complete	—
12-3	500 hrs performance, X-2 cylinders.	$23,133.00	$22,180.52	Complete	—
12-4	1,000 hrs X-7 performance and calibration.	$77,162.00	$72,356.53	Complete	—
12-5	300 hrs on X-7 150-hr test.	$23,146.00	$6,519.93	Complete, cost not fully reported.	—
12-7	Design of various reduction gear units.	$94,761.00	$71,311.13	Complete	—
12-10	Parts to complete two reduction gear units of 12-7.	$139,819.00	$9057.54	Continue	Continue
12-11	Build an XR-7755-1 from 12-8 and a -5 from 12-8, 10 and 11; 300 hrs testing.	$175,780.00	$38,218.76	Continue	Continue
12-12	150 hrs including acceptance tests on engines of 12-11.	$68,697.00	$10,648.15	Continue	Stop
12-13	500 hrs continuation of 12-4.	$35,890.00	$23,270.88	Complete	—
12-14	500 hrs continuation of 12-2	$35,890.00	$18,577.83	Complete	—
12-15	200 hrs continuation of 12-4	$14,357.00	$5,141.44	Complete	—

Letter Supl. Item	Final Supl. 7 Item	AFP Item	Work Called For	Estimated Cost	Actual Cost	Previous Status	Proposed Revised Status
12-2	1	2	2,500 hrs endurance, continuation of 12-2	$184,575.00	$242,612.30	Continue	Stop
12-4	2	3	2,500 hrs performance and calibration, continuation of 12-4	$184,575.00	$43.664.61	Continue	Stop
13	3	1	Assembly and 500 hrs nose-to-nose testing reduction gear from 12-10.	$100,464.00	$11,722.63	Continue	Stop
14	4	4	400 hrs including 50-hr (Spec 28144-A) on XR-7755-1 or -5.	$282,877.00	—	Not started	Continue on flight approval spec.
15	5	5	Build XR-7755-3 using parts from 12-8, 12-16; 100 hrs testing	$70,720.00	—	Not started	Stop, use for parts
16	6	6	100 hrs performance testing on XR-7755-3 or -5	$70,720.00	—	Not started	Stop
			Adjustment with AAF auditor on amount for overhead and estimated General & Administrative		$133,281.61.
			Inventory not allocated to items		$628,459.62
			Totals	$4,545,506.00	$3,090,411.26
			Estimated allowance for December 1946 and January 1947		$156,000.00
			Estimated total as of 1 February 1947		$3,246,000.00
			Remaining funds = $4,545,506.00 - $3,246.000.00 ≈ $1,300,000.00 as of 1 February 1947.

Work Status
Item	Work Called For	Dec 1945	Jul 1946	Oct 1946	16 Dec 1946
1	Build four 1-, 3-, 4-cyl engines, run perf tests	† Building 3- and 4-cyl remains	†	†	†3-cyl built, 4-cyl remains
2	1-cyl perf tests on other cyls	‡	‡	‡	‡
3	1-cyl end tests on other cyls	‡	‡	‡	‡
4	XR-7755-1 Design, blueprints, design reports	BPs rcvd, rpts in work	‡	‡	‡
5	XR-7755-1 Mock-up	‡	‡	‡	‡
6	Partly-finished parts for three XR-7755-1s	‡	‡	‡	‡
7	Three sets rough forgings, castings, bearings	‡	‡	‡	‡
8	Special tests on components, etc.	Continuing	Continuing	Continuing	Continuing
9	X-24 and BX engine tests	Complete except for running on new dyno	‡	‡	‡
10	3 fuel inj pumps, 36 nozzles	3 injectors and 8 nozzles delayed	‡	‡	‡
11	Fuel inj set for XR-7755-1	3 injectors and 8 nozzles delayed	‡	‡	‡
Ex 1 12-1	X-7: 200 hrs on 50-hr end test	‡	‡	‡	‡
Ex 1 12-2	X-7:2,000 hrs end	‡ Reports in prep	‡	‡	‡
Ex 1 12-3	500 hrs perf, X-2 cylinders	‡ Reports in prep	‡	‡	‡
Ex 1 12-4	X-7: 1,000 hrs perf and calib	‡ 79,9 grs renaububg	‡	‡	‡
Ex 1 12-5	X-7: 300 hrs on 150 hr test	No testing yet		Testing started	‡
Ex 1 12-6	XR-7755-1 design; cont of Item 4	BPs rcvd; dsn reports in work		Most complete, some redesign	Some redesign
Ex 1 12-7	Reduction gear unit design	Dsn complete, parts in process, no BPs		In work
Ex 1 12-8	Continuation of Item 6	Finish parts for one engine		In work
Ex 1 12-9	One set finished XR-7755-1 parts			In work
Ex 1 12-10	Parts for 2 reduction gears	See 12-7		In work
Ex 2 12-11	Build XR-7755-1 from 12-8, -10; 300 hrs testing	Build started		1 built, testing started
Ex 2 12-12	150 hrs including accessory tests on 12-11	No work started		1 built, testing started
Ex 3 12-13	500 hrs continuation of 12-4	Reports in prep		‡	‡
Ex 4 12-14	500 hrs continuation of 12-2	Reports in prep		‡	‡
Ex 5 12-15	200 hrs continuation of 12-4	143.8 hrs accomplished		‡	‡
Symbols: † = Testing complete; ‡ = Item complete; X = Open test item

Work Status
Letter Supl. Item	Final Supl. 7 Item	AFP Item	Work Called For	Dec 1945	Oct 1946	16 Dec 1946
13	3	1	Assembly and 500 hrs nose-to-nose testing reduction gear from 12-10.	No work	No work	No work
12-2	1	2	2,500 hrs endurance, continuation of 12-2	No work	665.8 hrs	688.9 hrs
12-4	2	3	2,500 hrs performance and calibration, continuation of 12-4	181.6 hrs0	804.9 hrs	976.0 hrs
14	4	4	400 hrs including 50-hr (Spec 28144-A) on XR-7755-1 or -5.	No work	No work	No work
15	5	5	Build XR-7755-3 using parts from 12-8, 12-16; 100 hrs testing	No work	Starting subassys	No work
16	6	6	100 hrs performance testing on XR-7755-3 or -5	No work	No work	No work

[RG 342 RD2311. XR-7755 Contract W-33-038AC-564. Summary of Work & Status. 002-008.]

15 Jan 1947. Blackwood wrote Lycoming outlining changes the XR-7755 Contract W-33-038 ac-564.

The Air Materiel Command is revising its program on subject contract and finds it necessary to stop action on the currently proposed procurement for building an additional engine and initiating studies and development of the compounded version of the XR-7755 engine.
Further, the Air Materiel Command will not be in a position to extend the basic contract work beyond the amount already obligated. Therefore, contract modifications are being immediately considered for the purpose of insuring that a 50-hr flight approval test in accordance with AAF Specification XR-28398-A is completed even at the expense of sacrificing other items on the contract. It is desired to eliminate, or hold in abeyance, items pertaining to future development in order to funnel remaining funds into the accomplishment of this 50-hr test with a minimum of accompanying development. This may mean a modified rating for this test, if deemed necessary since it is to be accomplished essentially with engines and parts now available.
The tentative proposed contract modifications are as follows:
1. Item 1 – Stop further building 1-, 3- and 4-cylinder engines. This would end work on this item.
2. Item 7 – Stop further procurement of these rough forgings, castings and bearings.
3. Item 8 – Stop all tests except possibly a few in conjunction with 50-hr test problems and those tests to be mutually agreeable to Lycoming and the Air Materiel Command.
4. Item 12-6 – Stop design unless mutually agreed on some 50-hr test problem.
5. Item 12-9 – Stop work.
6. Item 12-12 – Stop work.
7. Supplement #7, Item 1 – Stop work.
8. Supplement #7, Item 2 – Stop work.
9. Supplement #7, Item 3 – Stop work.
10. Supplement #7, Item 4 – Change test specification from AAF No. 28144-A to AAF Specification No. XR-28398-A dated 18 Mar 1944.
11. Supplement #7, Item 5 – To be deferred pending outcome of 50-hr test..
12. Supplement #7, Item 6 – Cancel.
Items 2, 3, 4, 5, 6, 9, 12-1, 12-2, 12-3, 12-4, 12-5, 12-7, 12-13, 12-14 and 12-15 have been completed. Therefore, summarizing, this means that some slight amount of work may be permitted under Items 8 and 12-6, that Items 10, 11, 12-8, 12-10, 12-11 will be unaffected and that Supplement #7, Item 4 will be retained except the test is to be run to the 50-hr flight approval test specification.
Before any of the above program is put into effect, it is suggested that Lycoming representatives come to Wright Field to discuss this program in detail and offer suggestions towards the goal of achieving a 50-hr test and having an engine ready for flight status with what funds remain on the contract. It is felt that concentrating on this achievement will put the engine in the most favorable position for the possibility of a later re-activation of the project. Your early suggestions as to a suitable conference date are requested.

[RG 342 RD2311. XR-7755 Contract W-33-038 ac-564. Proposed Procurement and Mods. 470115031-032.]

27 Jan 1947. Associated with the 15 Jan 1947 Stop-Work order was the following estimate of contract completion cost as of 1 Feb 1947:

Item 8	Special tests including necessary test fixtures and parts relating to XR-7755-1 engine development.		$70.000.00
Items 10, 11	Fuel injection equipment procurement.		$40,000.00
Item 12-8	Completion of three parts sets for XR-7755 initiated under Item 6.		$240,000.00
Item 12-10	Two sets of reduction gear units selected from Item 12-7.		$114,819.00
Item 12-11	Build two XR-7755 multi-cylinder engines and perform a minimum of 300 hrs testing.
	Engine buildup	$13,202.00
	Parts design and procurement	$50,870.00
	Test	$121,968.00
		–––––––––––
		$186,040.00
	5% Administrative	$9,302.00
		–––––––––––
		$195,342.00
	4% Fee	$7,813.00	$203,155.00
Supp. #1, #2	Design, parts and 1,500 hrs endurance and performance testing of single- and three-cylinder engines.
	Test: 1,500 hrs @ $52.65	$78,975.00
	Parts @ $15.00 per hr	$22,500.00
	Design	—
		–––––––––––
		$101,475.00
	5% Administrative	$5,074.00
		–––––––––––
		$106,549.00
	4% Fee	$4,262.00	$110,811.00
Supp. #3	50-hr nose-to-nose reduction gear test and two-speed shift control
	Redesign	$15,000.00
	Test	$47,000.00
	Parts	$20,000.00
		–––––––––––
		$82,000.00
	5% Administrative	$4,100.00
		–––––––––––
		$86,100.00
	4% Fee	$3,444.00	$89,544.00
Supp. #4	Necessary redesign, parts and 400 hrs testing to include a satisfactory 50-hr development test conducted in accordance with Air Corps Specification 28144-A.
	Redesign	$13,800.00
	Parts	$116,100.00
	Test	$128,800.00
	Gas and Oil	$64,800.00
		–––––––––––
		$323,500.00
	5% Administrative	$16,175.00
		–––––––––––
	4% Fee	$13,587.00
			$353,267.00
			$1,221,596.00

[RG 342 RD2311. XR-7755 Contract W-33-038 ac-564. Proposed Procurement and Mods. 470127037.]

29 Jan 1947. A conference at Wright Field included Cols Minty and O'Keef, Blackwood, Chenoweth, Wolfe and Ahern from the AMC; Posthauer, Guibord, Carpenter and Riddell from Lycoming. This was a follow-up to Blackwood's 15 Jan 1947 reference letter.

Lycoming submitted the following:

In accordance with the contents of the reference letter, the following proposal is submitted outlining the work to be done under various contract items to accomplish the 50-hr flight approval test. Items not specifically mentioned have been completed.

Item 1: All test work and building of the two single-cylinder engines and the three-cylinder engine have been completed. The only remaining item of work, building the four-cylinder engine, will be stopped.

Item 7: Procurement of additional rough forgings, castings and bearings will be stopped.

Item 8: Special tests, including necessary test fixtures and parts, shall be run if required for satisfactory accomplishment of the prescribed XR-7755 flight approval test. The following are tests that may be necessary under this program

a) Bench test of fuel injection equipment.
b) Torque meter and torque meter pump test.
c) Fatigue test of crankshaft test piece having clutch teeth at center of crankpin.
d) Stresscoat test of crankshaft.
e) Oil scavenge pump tests.
f) Supercharger efficiency and distribution tests.
g) Fatigue test of link pins.

Items 10, 11: Procurement of fuel injection equipment under these two items will not be affected.

Item 12-6: Initial design of the engine section covered by this item has been completed. Further design work to improve the engine will be stopped. Redesign of parts dictated by engine tests will be accomplished under the pertinent test items.

Item 12-9: Work on the parts set call for under this item will be stopped.

Item 12-10: The two reduction gear units covered by this item will be completed.

Item 12-11: The provisions and requirements of this item will be retained as originally prescribed.

Item 12-12: Work toward accomplishment of the acceptance tests of the two engines built under item 12-11 will be stopped.

Supplement 7, Items 1, 2: Work under these two items will be combined and curtailed to perform 1,500 hrs endurance and/or performance testing of the single- and three-cylinder engines in conjunction with problems arising from the testing of the XR-7755 engine.

Supplement 7, Item 3: Retain the provisions for this item calling for necessary redesign, parts and testing of the two reduction gear items built under item 12-10.

Supplement 7, Item 4: The requirements of this item, revised to include a 50-hr test under AAF Specification No. XR-28398-A (18 Mar 1944), instead of the AAF Specification No. 28144-A originally called for, will be accomplished.

Supplement 7, Item 5: Work under this item will be stopped pending outcome of the above 50-hr test.

Supplement 7, Item 6: The requirements of this item will be cancelled.

[RG 342 RD2311. XR-7755 Contract W-33-038 ac-564. Proposed Procurement and Mods. 470129035-036]

During the course of the conference, Blackwood's hand-written notes revealed several things that do not appear in the official correspondence:

Lycoming agreed to run tests on dual-rotation two-speed reduction gear nose after the 50-hr test was complete.
A total of 1,700 hrs multi-cylinder running was accomplished or proposed.
Lycoming was doing only those things that would accomplish the 50-hr test.
Lycoming requested further work along other (non-XR-7755) lines help keep the development and experimental organizations working.
Testing in accordance with Specification No. XR-28398-A (18 Mar 1944) paragraph F.F.1 was to be at the Contractor's plant.
All running was to be on a sea level test stand; no back pressure capability.
The 3-cylinder engine had achieved the following performance:

rpm 1,600 2,200

imep (psi) 146 151

isfc (lb/ihp/hr) 0.336 0.341

ihp 189.5 273.0

[RG 342 RD2311. XR-7755 Contract W-33-038 ac-564. Proposed Procurement and Mods. 470129033-034]

8 Mar 1947. During a telcon with Posthauer and Carpenter, Blackwood advised them that 8-9 months of funds were left in contract W-33-038 ac-564. It appeared Item 14 would complete early, which meant that work on Items 13 and 15 could be released. [Penciled notes by J.G. Blackwood. RG 342 RD2311 XR-7755, 1943-1948: 503-602 Conf and Tel Notes. 470308889.]

1 May 1947. AMC Contracting officer Robert W. Logan cabled Lycoming a contract termination notice with copies to the New York Army Air Forces Procurement Field Office (AAFPFO) Readjustment Section, and to Lt Col E.L. Quick, Procurement Division Readjustment Section Chief. The telegram read:

Your Contract No. W 33-038 ac-564 is hereby terminated in part for the convenience of the Government pursuant to Article 5 thereof, effective immediately, by omitting that portion of the work covered by subject contract as follows: Undelivered balance of Item 1; Item 7; Item 16; Item 12-9 of Exhibit 1 and Item 12-12 of Exhibit 2. You are instructed to immediately stop all work, terminate subcontracts and purchase orders, and place no further orders in connection with the terminated portion of the contract or work to be omitted, except to the extent that you or a subcontractor or supplier wish to retain and continue for your account any work in process or other materials. Telegraph similar instructions to all subcontractors and suppliers. This notice is not applicable to items previously shipped and no shipments of the terminated items shall be made after the receipt of this notice. Shipping instructions for completed items that are terminated will be furnished by your contracting officer. Letter and instructions follow. Request you contact Chief, New York AAF Procurement Field Office, Attention Termination Officer, 67 Broad Street, New York 4, New York for any information in conjunction herewith. Wright Field Docket No. 29579. Signed Robert W. Logan, Contracting Officer.

[RG 342 RD2311. XR-7755 Contract W-33-038 ac-564. Proposed Procurement and Mods. 470501027-028.]

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rpm	1,600	2,200
imep (psi)	146	151
isfc (lb/ihp/hr)	0.336	0.341
ihp	189.5	273.0