On each of the first Five Thousand (5,000) such engines produced and sold in any one calendar year, the royalty shall be at the rate of Twenty-five Cents ($.25) per horsepower; and on all over Five Thousand (5,000) in such calendar year, at the rate of Ten Cents ($.10) per horsepower;
provided that, after a total of Fifty Thousand Dollars ($50,000.00) has been paid in royalties the royalties shall be reduced one-half (½).
11. After the beginning of the second year of production, Licensee agrees that if the royalties under the above schedule amount to less than Ten Thousand Dollars ($10,000.00) per year then the royalty shall be Ten Thousand Dollars ($10,000.00) per year payable in quarterly instalments of Two Thousand Five Hundred Dollars ($2,500.00) each, or in other words, the minimum royalty payable shall be Ten Thousand Dollars ($10,000.00) per year.
12. Royalties shall continue only during the life of said patent Number 1,628,657, and when a total of Two Hundred Fifty Thousand Dollars ($250,000.00) has been paid by Licensee to Licensor, all royalties shall cease and the license hereunder shall be free thereafter.
13. Licensor agrees that Licensee shall have the benefit of any more favorable royalty rates that may be hereafter granted to or enjoyed by any other manufacturer of engines other than aircraft engines.
14. Licensee agrees to keep proper books of account showing the number of engines manufactured and sold or used under this agreement and to report quarterly to Licensor.
15. In case of suit against the Licensee for infringement of patents by any of the Dorner features built under this license Licensor agrees to assist in the defense of any such suit and pay the expenses thereof up to an amount equal to Ten Percent (10%) of all royalties paid by Licensee to Licensor hereunder.
16. In event of default of the Licensee in the payment of any of the sums herein provided for, Licensor may terminate this license agreement by serving upon the Licensee Sixty (60) days’ notice in writing of its desire and determination so to do and stating the default upon which the notice is based, and at the expiration of such Sixty (60) days this license shall thereupon be terminated, provided however that such termination shall not release the Licensee from obligations already accrued hereunder and not performed, and provided further that if, during said Sixty (60) days’ notice period, the default named in said notice shall have been made good then this license to continue as if no default and notice had been made or given.
17. At the expiration of any one year from November 1, 1929, Licensee may terminate this agreement upon Sixty (60) days’ notice in writing to Licensor of its desire and determination so to do, provided however, that such termination shall not release the Licensee from obligations already accrued hereunder and not performed.
18. In case of differences of opinion regarding any of the terms of this agreement, the dispute shall be submitted to arbitration. Each party shall select one arbitrator and if they, after five days, fail to agree upon a third, the United States Court for the Detroit District shall be asked to appoint such a third arbitrator, and the decision of a majority of the arbitrators shall be binding upon both parties.
In witness whereof, we have hereto set our hands and seals at Detroit, Michigan, on the day and year first above written.
Witnesses—(Signatures):
Hermann Dorner
L. A. Wright
Adolf Widmann
packard motor car company
Alvan Macauley
President
(Seal)
Attest: Milton Tibbetts
Assistant Secretary
Will Start Construction at Once on New Three Story Factory to Handle Work
[From Aviation, March 2, 1929, vol. 26, no. 10]
DETROIT, MICH.—Indications that the Diesel type airplane engine, recently developed by Capt. L. M. Woolson, chief aeronautical engineer of the Packard Motor Car Co., will become a commercial reality and possibly a revolutionary factor in airplane engine design, is seen here in the announcement of the concern that it will begin construction immediately of a $650,000 plant to produce the engines in large quantity for the commercial market.
The new plant, according to the announcement by Hugh J. Ferry, treasurer of the Packard firm, will be completed and in operation within five weeks. Between 600 and 700 men will be employed and, according to expectations, production will be carried on at the rate of about 500 Diesel engines per month by July.
The Packard Diesel was announced first in October, following experiments covering several years. The original engine was placed in a Stinson-Detroiter, which was flown successfully by Captain Woolson and Walter Lees, Packard pilot. Since that time Captain Woolson has built four of the engines, all of 200 hp. capacity, developing 1 hp. for every 2 lb. of weight.
The Diesel, installed on the Stinson-Detroiter, it was said, now has had 200 hr. flying time, and gives not the slightest indication that it will need an overhauling for some time. The other three engines have been tested on the block in the company’s research plant.
It is claimed by the builders that the Packard Diesel will produce a saving of about 20 per cent. in fuel consumption as compared with engines using gasoline. It is claimed further that the Diesel will prove far more reliable in construction than any airplane engine yet developed. Evidence of this, it was pointed out, is seen in the performance of the initial Diesel.
Details Not Announced
Although neither Mr. Ferry, nor Captain Woolson, would disclose any technical details as to the engine’s construction in making it applicable to airplane use, the secret of its success was reported to be an especially designed pumping device creating high compression necessary for Diesel firing.
Since announcement of the engine, the Packard factory has been literally a Mecca for engineers from many parts of the world wishing to see the engine. The Crown Prince of Spain, in Detroit last fall, was given a flight in the Diesel powered Stinson. None of the construction secrets, however, have been divulged, it was said.
The Packard announcement set at rest rumors that the company planned construction of a plant costing several million dollars, as well as reports that the company was going into the production of airplanes. “Our efforts,” Mr. Ferry said, “will be confined to the engine, or power plant end of the aircraft industry. We will continue to build the water-cooled type we have been producing for years.” The new Diesel plant will be primarily an assembly plant, although some machine work will be done there. The bulk of the machine work, however, will be done in the present Packard machine shops.
Although no approximation of selling price on the new Diesel was divulged, it was intimated that the engine will retail at a price competitive with or slightly under the price of present gasoline consuming air-cooled engines of that horsepower range. Captain Woolson will have complete charge of the Diesel plant, it was announced.
[From P. H. Schweitzer and E. R. Klinge, “Oxygen-Boosting of Diesel Engines for Take-Off,” The Pennsylvania State College Bulletin (April 1, 1941), vol. 35, no. 14, p. 25.]
Practical Conclusions
Airplanes require about one third more power during the take-off than in flight. In diesel-engined airplanes the size of the engine could be reduced by 25 percent by feeding oxygen into the intake air during the takeoff. Applying the results of the experiments to a transport plane, Fig. 31 shows the possible weight saving with various oxygen boosts. The curves are based on 6000 cruising horsepower and an estimated engine weight of 2 lb per hp.
For the take-off 8000 hp are necessary. To supply the additional 2000 hp, 200 lb of oxygen are fed into the intake air during the take-off. The volume of 200 lb of liquid oxygen is approximately 20 gal. Standard liquid air containers of 55 litre capacity weigh 75 lb. Therefore the weight of the oxygen and container is 350 lb while the possible saving in engine weight is 4000 lb. The weight per take-off horsepower is thereby reduced from 2 to 1.54 lb. The calculation is shown in Table 1.
| Figure 38.—Effect of Oxygen Boost on Power and Weight. (Cruising horsepower 6000, takeoff horsepower 8000.) |
Oxygen addition may be used for starting diesel engines. The raising of the oxygen concentration from the normal 21 per cent to 45 per cent was found to be equivalent to a raise of approximately 10 cetane numbers as far as starting is concerned.
Five per cent increase in oxygen concentration eliminated exhaust smoke completely.
Table 1
| Normal horsepower | 6000 |
| Take-off horsepower | 8000 |
| Normal fuel consumption | 0.4 lb per hp-hr, or 53.5 lb per min |
| Normal air consumption | 900 lb per min |
| Normal oxygen consumption, 21 per cent oxygen concentration | 189 lb per min |
| Boosted oxygen consumption, 32 per cent oxygen concentration | 289 lb per min |
| Oxygen to be supplied | 100 lb per min |
| Weight of 8000-hp engine | 16,000 lb |
| Weight of boosted 6000-hp engine | 12,000 lb |
| Weight of oxygen for 2-min boost | 200 lb |
| Weight of container for 29 lb of liquid oxygen | 150 lb |
| Net weight saving by oxygen boost | 3650 lb |
| Weight per horsepower, nonboosted engine | 2 lb |
| Weight per horsepower, boosted engine | 1.54 lb |
Footnotes:
[2] Letter, Hermann I. A. Dorner to National Air Museum, March 3, 1962.
[5] Aeronautics (October 1929), vol. 5, no. 4, p. 32.
[6] The Packard Diesel Aircraft Engine—A New Chapter in Transportation Progress (Detroit: Packard Motor Car Co., 1930), p. 5.
[7] A memorial to Woolson who was killed in the crash of a Packard diesel-powered Verville “Air Sedan” on April 23, 1930.
[8] Packard Inner Circle (April 18, 1932), vol. 17, no. 6, p. 1.
[9] Aero Digest (February 1932), vol. 20, no. 2, p. 54.
[10] Letter, Richard Totten to National Air Museum, January 28, 1964.
[11] Instruction Book for the Packard-Diesel Aircraft Engine (Detroit: Packard Motor Car Company, 1931), p. 3.
[12] S.A.E. Journal (April 1930), vol. 24, no. 4, pp. 431 and 432.
[13] Letter, Richard Totten to National Air Museum, January 28, 1964.
[14] Letter, Hermann I. A. Dorner to National Air Museum, December 16, 1961.
[15] The National Aeronautic Magazine (April 1932), vol. 10, no. 4. p. 18.
[16] Aviation (May 1931), vol. 30, no. 5, p. 281.
[17] The Packard Diesel Aircraft Engine, p. 5.
[18] Instruction Book for the Packard-Diesel Aircraft Engine, p. 3.
[19] “Test of Packard-Diesel radial air-cooled engine,” Navy Department, Bureau of Aeronautics, Report AEL-335, July 13, 1931, Bu. Aer. Proj. 2265.
[20] Aviation (May 1931), vol. 30, no. 5, p. 281.
[21] Letter, Clarence H. Wiegman to National Air Museum, November 1, 1961.
[22] Letter, Dorner to National Air Museum, January 15, 1962.
[23] Letter, Hugo T. Byttebier to National Air Museum, October 20, 1961.
[24] Letter, Clarence D. Chamberlin to National Air Museum, February 8, 1964.
[25] Ruth Nichols, Wings For Life (Philadelphia and New York: J. B. Lippincott Co., 1957), p. 205.
[26] Letter, Richard Totten to National Air Museum, January 28, 1964.
[27] Letter, Richard Totten to National Air Museum, January 28, 1961.
[28] Aero Digest (February 1931), vol. 18, no. 2, p. 58.
[29] “50-Hour Test of Packard Diesel Aircraft Engine,” Packard Motor Car Company, Detroit, Michigan, serial no. 426, test no. 234-73, February 19, 1930.
[30] Blower in this sense refers to a low-pressure air pump (supercharger) designed to increase cylinder scavenging efficiency by blowing out exhaust gasses. In doing this it also increases somewhat the amount of fresh air introduced into the cylinders. Woolson invented a 2-stroke cycle blown engine; the patent was issued in 1932 (patent 1853714) with rights assigned to the Packard Motor Car Company. (Woolson himself died in 1930.)
[31] A 2-stroke cycle engine completes 360° of crankshaft rotation in what it takes a 4-stroke cycle engine 720° to accomplish. A 3-cylinder two-stroke cycle engine therefore has the same capacity to do work as a 6-cylinder four-stroke cycle engine. For this reason the former type of engine is both more compact and lighter than the latter type.
The above advantages, plus the increased efficiency of the blown 2-cycle diesel, are discussed in Flight—The Aeronautical Engineer Supplement (December 26, 1940), vol. 19, no. 11, pp. 545 and 552.
[32] Packard advertisement—Aero Digest (June 1930), vol. 16, no. 6, p. 23.
[33] Aviation (March 15, 1930), vol. 28, no. 11, p. 531.
[34] The National Aeronautic Magazine (April 1932), vol. 10, no. 4., p. 18.
[36] See Woolson’s patent 1794047, issued in 1931 and assigned to the Packard Motor Car Company. “An object of my invention is to automatically regulate the compression ratio in an engine inversely to the speed....” See also his patent 1891321, issued in 1932 and assigned to the Packard Motor Car Company. It describes a similar but nonautomatic system. Woolson therefore fully realized the disadvantages of the high cylinder pressures his engine developed at high rpm’s.
[37] Letter, Clarence H. Wiegman to National Air Museum, November 1, 1961.
[38] Ibid.
[39] Major George E. A. Hallet, U.S. Air Service, former director of engineering division, McCook Field, Dayton, Ohio.
[40] “Test of Packard-Diesel radial air-cooled engine,” Navy Department, Bureau of Aeronautics, Report AEL-335, July 13, 1931, BuAer Proj. 2265.
[41] Aviation Week and Space Technology (February 19, 1962), vol. 76, no. 8, p. 101.
[42] Aeronautics (October 1929), vol. 5, no. 4, p. 31.
[43] Letter, Richard Totten to National Air Museum, January 28, 1964.
[44] According to Frederic E. Hatch of the National Air Museum, it is possible that the engine failed because the fuel injectors became clogged. He notes that the airplane refueled at several fishing ports, and therefore must have used diesel oil set aside for fishing boats. This oil was generally quite dirty. As a result it was routine for the fishermen to have to clean engine oil filters frequently enroute. The oil filters of the Packard diesel could not be cleaned in flight.
Transcriber’s Notes:
Other than the corrections noted by hover information in the text, printer’s inconsistencies in spelling, punctuation, and hyphenation usage have been retained.