In the post-war civil fleet, one of the most vital tasks performed by the B-17 was that of an aerial tanker, something the airplane did quite well through the 1960s and 1970s. It was part of a varied and oddball fleet of other surplus World War II bombers and fighters. But the demanding requirements of carrying heavy loads of fire retardant in high density altitude conditions through the rugged terrain of the western U.S. often kept air tankers, B-17 included, on the ragged edge of marginal performance. In 1970 one air tanker operator, the Elgin brothers of Cody, Wyoming, took a hard look at the shrinking supplies of Wright Cyclones and the advantages of turboprop engines, and decided to re-engine their pair of B-17 tankers with Dart turboprops. This is the story of that effort and, though it doesn’t have a happy ending, adds one more chapter to the diverse history of the Flying Fortress.
B-17F 42-6107
Vega, a subsidiary of Lockheed, built 500 B-17Fs and 2,250 B-17Gs between June 1942 and August 1945. B-17F s/n 42-6107 was delivered at Burbank on July 23, 1943, and was immediately flown to nearby Long Beach for after-production modifications. It was then delivered to Dalhart, Texas, to be stored in a depot until assigned to a training unit at Galveston Army Air Field (AAF), Texas, with the Second Air Force in October 1944. Its initial assignment was with the 202nd Army Air Base Unit at Galveston. 42-6107 was redesignated as a TB-17F for the training role, probably either towing targets for aerial gunners in training or serving as a training platform. It served at Galveston until, evidently, March 1945, when it was briefly assigned to Ardmore AAF, Oklahoma, before going to nearby Altus AAF. At Altus, it was transferred to the RFC for disposal on November 7, 1945.
Postwar: 42-6107 as an Educational Aid
In 1946 it was transferred by the RFC to the Washington State Department of Public Instruction at Clarkston, Washington, for educational use. Clarkston is located on the extreme eastern edge of Washington State, just across the Columbia River from its sister city, Lewiston, Idaho, the heritage of Lewis and Clark who passed through nearly two centuries earlier not being lost on the locals. The B-17F was delivered to Clarkston in 1946 and was probably used as a technical training aid for the next several years. Its condition deteriorated quickly, though, and by the early 1950s it was quite derelict and something of an eyesore at the airport.
Sale to Columbia Airmotive
Columbia Airmotive was based at Troutdale, Oregon, located about fifteen miles east of Portland up the Columbia River. Bob Sturges, who had served as a Boeing technical representative during World War II, specializing in B-17s, owned Columbia Airmotive. Sturges purchased much of Boeing’s surplus stocks of B-17s after its production line had shut down, making Sturges and his company a primary source of spares for B-17s in the immediate post war years. Sturges also dealt in whole airplanes, and he was able to obtain several airframes, one of which was 42-6107. By 1953, the Department of Public Instruction was willing and eager to part with the airplane, and Sturges made an offer to take it off its hands. In the deal, Sturges paid the state of Washington $16,600 (not as cheap as it sounds: $186,000 in 2022 dollars), of which $16,499.02 was forwarded by the state to the U.S. government in order to secure a release of the title. On November 17, 1953, the Department of Health, Education, and Welfare released the government’s interest in the airplane, and the following day the state of Washington sold it to Columbia Airmotive. The state earned a cool $100.98 on the deal, but got rid of its little problem parked at the Asotin County Airport at Clarkston.
Sturges and a team of mechanics arrived to put the tired B-17 back in airworthy condition, at least enough to get the airplane to fly 100 miles down the Columbia to Troutdale. The airplane was in such bad condition that it took nearly three months to get it airworthy. In the meantime, on December 7, 1953, the ownership was transferred from Columbia Airmotive to another company owned by Sturges and Morris Greenstein named Aero Enterprises. The CAA reserved the civil registration of N1340N for the airplane, officially assigning it to the airplane four days later.
N1340N Converted to an Air Tanker
It remained stored at Troutdale for the subsequent four years. In 1958 it was rebuilt to airworthy condition, but its use in the following three years is unknown. No airworthiness certificate was issued by the CAA. By 1961, however, it was being leased by Mel Lengren from Aero Enterprises. In July 1961, Lengren took the airplane to Klamath Aircraft at Klamath Falls, Oregon, with the directions to install bomb bay tanks and convert the airplane into what was then known as a borate bomber. That work was completed in late July and a restricted airworthiness certificate was issued allowing operations in forest and wildlife conservation work. Records at that time show the airplane had officially logged 1,742 hours of flight time, much deflated no doubt and probably not including much of its military flight time. The airplane became Tanker A34 and it was added to the list of air tankers under contract with the U.S. Forest Service in their annual battle against forest and range fires, initially assigned to the states of Idaho, Washington, and Montana.
On July 28, 1964, N1340N was sold by Aero Enterprises, Oregon Corporation, to Aero Enterprises, a California corporation. How these companies were tied together, if at all, is unknown. However, the president of Aero Enterprises, located at Willows, California, was Willis “King” Baker, a figure who played prominently in the air tanker business in California for many years. Subsequently, the airplane was assigned to the Forest Service’s California region, becoming Tanker E34. It was largely based at Fresno for its tanker operations, but would come to be based at any number of tanker bases in the western U.S. depending upon the arrangements of the annual Forest Service air tanker contracts.
N1340N to Aero Flite of Cody, Wyoming
On January 19, 1968, N1340N was sold to Aero Flite of Cody, Wyoming. Aero Flite was an air tanker outfit that operated another B-17 tanker, B-17G N9323R (s/n 44-85828, an ex USCG PB-1G), that it had purchased in 1964. The company was owned by brothers John and J. Ray Elgin, both pilots and also operators of Elgin Flying Service at Cody. N1340N was again assigned to the Forest Service’s northwest region and designated as Tanker A34.
Aero Flite Proposes to Re-engine N1340N with Dart Turboprops
The airplane flew for Aero Flite for the 1968 and 1969 fire seasons. Then, prior to the 1970 season, company president Ray Elgin decided to undertake a radical transformation of N1340N. Even in the late 1960s the availability of suitable and affordable Wright R-1820 engines was becoming limited, and the opportunity presented itself to re-engine both Aero Flite B-17s with turboprop engines. There were three big advantages to fitting the B-17 with turboprops: engine maintenance would be significantly reduced and aircraft performance would dramatically improve. It was easy to see that the airplane would be able to carry a heavier load of retardant, climb more quickly, provide for an increased margin of safety for engine out situations, and improve the reliability of the airplane. The Rolls Royce Dart 510-65 turboprop engines and Rotol R 130/4-20-4/12E propellers that powered the British Vickers Viscount was an obvious choice for the new power plant because of their proven record and availability. Ray Elgin located and purchased two surplus Viscounts that were available from United Airlines to provide the eight engines needed to convert their two B-17s.
An arrangement was made with Aviation Ventures, Inc. (AVI) at Twin Falls, Idaho, to do the conversion work. AVI was run by Harber “Pete” Lazoros, a veteran mechanic who had earlier worked on heavy air tankers at Greybull, Wyoming. Lazoros had constructed a large hangar at Twin Falls suitable to house a B-17 for the conversion work, so Elgin had one of the United Viscounts delivered to Twin Falls and brought the first conversion airframe, N1340N to Lazoros in early 1970 to begin the modification. The other Viscount was delivered to Cody and placed into storage pending the conversion of the second B-17.
Under the direction of Lazoros, the four Wright engines were removed. The four point engine hardpoints on the firewall were modified to accept custom designed six-point engine mounts for the Dart engines, with two additional hardpoints fabricated and added to the top of each of the four engine firewalls. The fuel system was altered with the installation of two inline fuel pumps per engine, and the engine controls were adapted by changing the tie rod ends to the Viscount type. The avgas fuel tanks were adapted to use jet fuel. The FAA was brought into the process early, with the local district office tracking the modifications. Engineering data was obtained from Boeing to accomplish detailed stress analysis of the installation. The intent was to secure a Supplemental Type Certificate (STC) from the FAA allowing additional conversions of B-17 airframes, a valuable authorization that could be then sold as a license to other operators seeking the advantages of turboprop power.
The aircraft was rewired to accommodate the Viscount wiring for engine and propeller indicators and controls. The Viscount cowlings were adapted with the addition of new cowling sections to tie the cowlings to the standard B-17 firewalls. As the work progressed, a steady stream of curious visitors made appearances in the hangar, including representatives of both Boeing and Rolls Royce who were interested to see the merging of their two products.
B-17 Flies with Turboprop Engines
The work was completed by early May 1970, and on May 5, Ray Elgin test flew the airplane, noting in the maintenance log that the “aircraft is controllable throughout its normal range of speeds and maneuvers and has no hazardous operating characteristics or design features.” The engine-out minimum control speed was determined to be 90 knots.
It should be noted that the takeoff power output of the Dart 510 was 1,600 shaft horsepower (shp), and the maximum continuous output was 1,356 shp. The Wright R-1820-97 produced 1,200 brake horsepower (bhp) at takeoff power, and its maximum continuous power output was 1,000 bhp. While shaft horsepower and brake horsepower are not equivalent, the Dart engines provided at least thirty percent more power to the airplane while weighing 3,000 pounds less than the Wright installation.
By this time, the regional office of the FAA was focusing on the conversion and a test flight regimen was developed. N1340N was issued a 90-day experimental airworthiness certificate to allow for test flights from Twin Falls to determine the soundness of the modifications. The test flights required ten hours of flying, part of which allowed a ferry flight from Twin Falls back to Cody. In the subsequent three months, the airplane was flown a total of 45 hours. During the test period the FAA was unable to schedule its required test flights so the FAA issued another 90-day experimental certificate on August 4, authorizing additional research and development testing and allowing ‘for hire’ use as an air tanker.
The U.S. Forest Service looked at the airplane and the test flight results and authorized the turboprop B-17 to carry up to 2,400 gallons of retardant in its bomb bay tanks, a 400 gallon increase over its piston powered competitors. More retardant meant larger contract fees, so the conversion began paying off as soon as the airplane hit the fire lines. For several weeks, the airplane was employed against several fires in the northwest, making appearances at Wenatchee, Washington, and other tanker bases and attracting a great deal of understandable attention. The Elgin brothers were excited about their project, John Elgin later recalled that the airplane “was really a performer,” with the ability to quickly climb to enroute altitudes in minutes leaving the conventional B-17 tankers far below and behind as they struggled for every foot with their heavy loads of retardant. N1340N took to returning from retardant drops with the two inboard engines shut down and feathered, a fuel conservation effort and perhaps a bit of a demonstration of the excess power of the turbo 17.
Tragic Crash of N1340N
However, the success was not long-lived. On August 18, 1970, N1340N was being employed against a fire on the Wind River Indian Reservation east of Dubois, Wyoming. After a full day of flying the two Aero Flite B-17s against the fires, the pair were back again at Cody to reload. John Elgin, though, had reached his legal flight time limit for the day so he helped his brother get N1340N loaded and ready for one more attack on the fire. In the late afternoon Ray Elgin and 23-year-old copilot John Bastian departed toward the south for the 65 mile flight to the fire. The B-17 circled around the fire and fell in behind a lead plane to follow it into a long ravine to where two drops were to be made, 1,200 gallons of retardant for each drop. The first run of the sortie was good and the spotter plane pulled off the run to proceed to a different part of the blaze. Elgin maneuvered the bomber back around to make a second drop, which also fell accurately to its target. During the pull-up maneuver, though, strong up and down drafts driven by a nearby ridgeline and a hot fire caused the low-flying bomber to roll sharply to the left, dragging its left wing dangerously close to the rugged terrain. The left wing slashed across a tree that severed twenty feet of outboard wing from the airplane. The bomber staggered, rolled over, and hit the ground to exploded in flames. Both Elgin and Bastian were killed instantly.
The subsequent official investigation determined that the density altitude at the time of the accident was 13,000 feet, with the air temperature near 90 degrees, turbulence from up and down drafts in strong surface winds, and smoke from the fire restricting visibility. It was, sadly, not an uncommon fate for men who undertake flying on the ragged edge of the envelope in the risky profession of aerial fire-fighting. Fifty-two years later it remains a tragic accident that killed two fine pilots and marked the end of the one and only Dart-powered B-17.
The Fate of the Dart Turboprop Modifications for the B-17
The STC was never completed on the modification, and N1340N was not insured so John Elgin was not able to proceed with a modification of N9323R. Numerous inquires were made from other tanker companies and B-17 operators in South America for conversion details, but without the STC there was no commercial value to the information. Eventually, the extra Viscount at Cody was sold. In 1975, N9323R was sold to another tanker operator, Bruce Kinney, of Richey, Montana, and then went into the USAF Museum collection. N9323R is now displayed as “I’ll Be Around” at the 390th Memorial Museum at Tucson, Arizona.
Aero Flite remained in John Elgin’s hands for another decade, until 1986, when the company was sold to Matt Ziomek, who moved it to Kingman, Arizona. The company later moved its base to Spokane, Washington, where it continues to provide air tanker services.
For more on B-17 air tankers, plus a whole lot of other stuff, see Final Cut: The Post-War B-17 Flying Fortress and Survivors.