Daily Archives: April 14, 2023

14 April 1986

General Dynamics F-111F Aardvark with 2000 pound GBU-10 Paveway II laser-guided bombs at RAF Lakenheath, 14 April 1981. (U.S. Air Force)
General Dynamics F-111F Aardvark with 2000 pound GBU-10 Paveway II laser-guided bombs at RAF Lakenheath, 14 April 1981. (U.S. Air Force)

14 April 1986: In response to several acts of international terrorism sponsored by the Libyan regime of Muammar Khadafi, the United States launched Operation El Dorado Canyon. Along with A-6E Intruders, F/A-18 Hornets and A-7 Corsair IIs from the aircraft carriers USS America and USS Coral Sea, 24 General Dynamics F-111F Aardvarks of the 48th Tactical Fighter Wing from RAF Lakenheath, accompanied by EF-111 Ravens for electronic counter measures, and flew 3,500 miles to their targets.

Navy aircraft attacked Benina Airfield and the Benghazi barracks, while the Air force fighter bombers, using GBU-10 Paveway II 2,000-pound laser-guided bombs, attacked the Aziziyah Barracks and the Sadi Bilal terrorist training camp at Tripoli. Because of the length of the flight, the F-111s had to refuel from KC-10 Extender air tankers four times in each direction. The KC-10s, in turn, refueled in flight from KC-135 Stratotankers.

There were very stringent rules of engagement in place, and for that reason, the majority of the Aardvarks did not release their bombs.

Libya had some of the most sophisticated air defenses in the world. Analysis indicated that only three cities in Russia were more heavily defended. Even so, of the 55 aircraft in the two attack forces, only one F-111 was lost, probably shot down by a surface-to-air missile. Its two man crew were killed.

A number of Libyan aircraft and facilities were destroyed. 37 people were killed and 93 wounded. From the standpoint of destruction caused, the results were minimal. But the effects on Colonel Khadafi were pronounced, and resulted in a significant scaling back of his regime’s terrorist activities. Viewed from that perspective, the mission was a complete success.

General Dynamics F-111F 70-2380, 48th Tactical Fighter Wing, with wings swept for high-speed flight, over a desert landscape. (U.S. Air Force)
General Dynamics F-111F 70-2380, 48th Tactical Fighter Wing, with wings swept for high-speed flight, over a desert landscape. (U.S. Air Force)

© 2015, Bryan R. Swopes

12–14 April 1985

The world record-setting Sikorsky S-76 Mark II, N1545X. The helicopter’s paint scheme has been updated since the world record flights in 1985. (MyFlightbook)

12–14 April 1985: Allison Gas Turbine Chief Test Pilot Frederick Jack Schweibold, along with company pilots Harry B. Sutton and R. Frederick (“Fritz”) Harvey, set a series of ten Fédération Aéronautique Internationale (FAI) world records for speed and distance, flying a Sikorsky S-76 Mark II, N1545X, which had been leased from Petroleum Helicopters, Inc., of Lafayette, Louisiana.

Contemporary news reports were that Schweibold and his crew, in addition to several PHI pilots, had actually set 15 speed, distance, and altitude records, but only ten world records are shown in the FAI’s online records database. The additional records may have been U.S. national records, but This Day in Aviation has been unable to confirm this with the National Aeronautic Association.

The Indianapolis Star reported:

(Frank Espich, The Indianapolis Star, 16 April 1985, Page 1, Columns 1–3)

Local Pilots set 15 world records in helicopter with Allison engine.

By Patricia Hagen

STAR STAFF WRITER

     Three local pilots set 15 world records in a commercial helicopter in two days, stopping only to refuel while flying more than 7,000 miles over the United States and Canada.

     The team from Allison Gas Turbine Division of General Motors Corp. started the marathon trip Friday evening in Lafayette, La. They set coast-to-coast, non-stop, altitude and speed records before inclement weather forced an early landing Sunday night in St. Louis.

     The trio was tired but excited when they finished the trip Monday afternoon at the Indianapolis Heliport in the Sikorsky S-76 Mark II helicopter powered by an Allison engine.

     The trip in the yellow and black craft was flawless, except for the early landing, said Jack Schweibold, Allison’s chief test pilot, who was dressed in tan coveralls and a company baseball cap.

     His teammates in the 35-foot helicopter were R. Frederick “Fritz” Harvey of Indianapolis, director of small-engine programs, and Harry B. Sutton of Pittsboro, staff pilot. The men have been involved in other record-setting flights in small airplanes and helicopters.

     The records set on this trip were for the heavy weight class of helicopters. The Allison team averaged 150 mph between Dallas and Montreal, Quebec, shattering the old record of 104 mph.

     On the way to Canada, they flew a record 950 miles non-stop before refueling in Toledo, Ohio.

     Then they cut several hours off the East Coast-to-West Coast record for this class of helicopters, going from New York City to Los Angeles in 19 hours, which included three stops for fuel.

     They also established speed records for climbs to 10,000 feet an 15,600 feet, said Schweibold, the official recorder on the flight.

     The records must be verified by the National Aeronautic Association in conjunction with the French aeronautics federation, the bodies that oversee challenges to air and space records. The pilots will receive awards at the Paris Air Show in June.

     The pilots managed only a few hours of sleep between turns at the controls of the helicopter, which could seat 14 passengers on a typical commercial flight.

     The only alteration to the $2.3 million helicopter for the weekend trip was a modified fuel tank, which added 200 gallons to the original 300 gallon capacity. About 4,100 gallons of aircraft fuel were burned in the 46 hours of flying time, the pilots estimated.

     The point of the record-setting blitz was to show the versatility of the Allison engine.

     “You can take a standard, stock Allison engine and expect to get championship performance,” Schweibold said.”We treated it like a stock Chevrolet.”

     The Allison model 250 engine is about the size of a car engine but develops 650 horsepower. The flight showed that it performs safely and with little maintenance even when used to challenge world records, Harvey said.

     “We’re bringing world-class aviation records to Indianapolis,” Harvey said. The Allison turbine engine division is proud of its reputation as a leader in engineering power plants for helicopters and turbo prop aircraft, he added.

     The trio of pilots plan to try for two other records before returning the aircraft, which they borrowed from Petroleum Helicopters Inc. in Lafayette, La., Harvey said.

     Over a 100-mile diameter circuit in Indianapolis,they will attempt an air speed record over 650 miles. They will also try to set a distance record on the course, which will entail going about 900 miles without stopping, Schweibold said.

The Indianapolis Star, Tuesday, 16 April 1985, Page 6, Columns, 1–3

The Indianapolis News,16 April 1985 at Page 26

In his own Internet blog, Jack Schweibold wrote that he picked up Harvey and Sutton in New York City before proceeding west to Los Angeles, with fuel stops at Indianapolis (8A4), Wichita (ICT), and Albuquerque (ABQ). The fuel stops took only about ten minutes each. They flew at 12,000 feet (3,658 meters) when crossing over the San Jacinto Mountains, east of Los Angeles, then passed overhead of the Seal Beach VORTAC (SLI) on the coastline south of Los Angeles.

While making a rapid descent to refuel at Riverside Airport (RAL), passing through 7,000 feet (2,134 meters), they heard two booms from the rear compartment. They checked the helicopter while refueling and everything seemed to be fine. They only filled the auxiliary tanks part way at Riverside, as they expected tail winds on the eastward leg.

The next fuel stop was at Saint Louis, Missouri. (Jack wrote that they didn’t land at Lambert Field (STL) because of adverse weather conditions, but did not specify where in St. Louis they did refuel.) They delayed their takeoff for New York waiting for improved weather conditions. When they finally went out to the helicopter, they found the S-76 surrounded by a pool of jet fuel about 200 feet (61 meters) across.

The two “booms” that the crew heard while descending in to RAL were caused by the auxiliary fuel tanks rupturing. They hadn’t leaked during the subsequent flight because the fuel level was kep below the fractures.

Jack’s full article can be found at: https://jetav.com/15-s76-records-set-in-week/

The records set by Schweibold, Harvey and Sutton were in the FAI’s Class E Rotorcraft, Sub-Class E-1 Helicopters, segments.

12 April 1985:

Speed Over A recognized Course, Dallas, Texas, to Indianapolis, Indiana. 268,56 kilometers per hour (166.88 miles per hour). FAI Record File Number 2067

Distance Without Landing, Dallas, to Toledo, Ohio.1 508,91 kilometers (937.59 statute miles). FAI Record File Number 1823

13 April:

Speed Over a Recognized Course, Dallas to Montreal, Quebec, Canada. 255,96 km/h (159.05 m.p.h.) FAI Record File Number 2068

Speed Over a Recognized Course, Indianapolis to Montreal. 244,44 km/h (151.89 m.p.h.). FAI Record File Number 2069

Speed Over a Recognized Course, New York, New York, to Indianapolis. 261,36 km/h (162.40 m.p.h.). FAI Record File Number 2070

14 April:

Speed Over a Recognized Course, Indianapolis to Wichita, Kansas. 254,88 km/h (158.38 m.p.h.) FAI Record File Number 2071

Speed Over a Recognized Course, Indianapolis to Albuquerque, New Mexico. 225,36 km/h (140.03 m.p.h.) FAI Record File Number 2072

Speed Over a Recognized Course, Indianapolis to Los Angeles, California. 202,68 km/h (125.94 m.p.h.) FAI Record File Number 2073

Speed Over a Recognized Course, Wichita to Los Angeles. 197,28 km/h (122.58 m.p.h.) FAI Record File Number 2074

Speed Over a Recognized Course, New York to Los Angeles. 209,52 km/h (130.19 m.p.h.) FAI Record File Number 2075

A 1984 advertisement for the Sikorsky S-76 Mark II. (Sikorsky Aircraft)

N5145X (s/n 760050) was a Sikorsky S-76 Mark II, an improved version of the original S-76A. There were more than 40 modifications to improve reliability and maintainability. In addition to new helicopters, the Mark II modifications were available as kits to update earlier S-76As.

The Mark II is a twin-engine intermediate class helicopter that can be configured to carry 6 to 12 passengers. It is used as an executive transport, a scheduled passenger airliner, utility transport, search and rescue aircraft and air ambulance. The helicopter is certified for instrument flight and has retractable tricycle landing gear.

The prototype was rolled out at Stratford, Connecticut on 11 January 1977 and the first flight took place on 13 March. It was certified in 1978 and the first production aircraft was delivered to Air Logistics, 27 February 1979.

Cutaway illustration of a Sikorsky S-76A. (Sikorsky Archives)

The S-76A is 52 feet, 6 inches (16.00 meters) long with rotors turning. The fuselage has a length of 43 feet, 4.43 inches (13.219 meters) and a width of 8 feet (2.44 meters). The helicopter’s overall height is 14 feet, 5.8 inches (4.414 meters). The four bladed composite main rotor is 44 feet (13.41 meters) in diameter. The blades are attached to a one-piece forged aluminum hub and use elastomeric bearings. As is customary with American helicopters, the main rotor turns counter-clockwise as seen from above. (The advancing blade is on the right.) The four-bladed tail rotor has a diameter of 8 feet (2.438 meters) and turns clockwise as seen from the helicopter’s left. (The advancing blade is below the axis of rotation.) It is mounted in a pusher configuration on the left side of the tailboom. The tail rotor is constructed of composite airfoils mounted to graphite spars.

The S-76 Mark II was equipped with two Allison 250-C30S turboshaft engines. The -C30S was capable of prodcing 650 shaft horsepower, but was derated to 557 shaft horsepower when installed in the S-76. Subsequent S-76 variants have been built with Turbomeca Arriel 1S and 2S engines, as well as Pratt & Whitney PT6B-3A and PW210S engines.

The S-76 has an empty weight of 7,007 pounds (3,178 kilograms). The S-76A maximum gross weight was 10,500 pounds (4,763 kilograms). Beginning with the S-67B, this was increased to 11,700 pounds (5,307 kilograms).

The Sikorsky S-76 has a maximum cruise speed of 155 knots (287 kilometers per hour). It can hover in ground effect (HIGE) at 7,050 feet (2,149 meters) or out of ground effect (HOGE) at 3,300 feet (1,006 meters). The service ceiling is 13,800 feet (4,206 meters).

The helicopter was designed with offshore oil support as a major consideration. It was intended to carry 2 pilots and 12 passengers 400 nautical miles (460 statute miles, or 741 kilometers). Maximum range with no reserve is 411 nautical miles (473 statute miles/762 kilometers).

Sikorsky built 307 S-76As. More than 850 of all variants have been built. The current production model is the S-76D.

N1545X’s FAA registration was cancelled 7 December 2016. The current status of the helicopter is not known. (TDiA did inquire with PHI, but the company did not respond.)

Petroleum Helicopters’ Sikorsky S-76 Mark II, N1545X. (Charlie Mauzé. Image used with permission.)

Jack Schweibold is currently credited with 29 FAI world flight records in both airplanes and helicopters.

Frederick Jack Schweibold was born at Toledo, Ohio, 8 November 1935, the son of Henry E. (a fire extinguisher salesman) and Jeanette Schweibold. He attended Thomas A. De Vilbiss High School, then Ohio State University where he majored in engineering. He had enlisted in the United States Naval Reserve in 1952 and then joined the United States Air Force as an Aviation Cadet in 1954.

Jack Schweibold with a North American Aviation T-28A Trojan.

Schweibold went through pilot training at Randolph Air Force Base, San Antonio, Texas, flying the T-34 and T-28. He went on to train in the B-25 at Reese Air Force Base, Lubbock, Texas. He was commissioned as a second lieutenant and received his pilot’s wings in July 1957. In a momentary decision, he selected helicopter training.

Frederick Jack Schweibold married Miss Sharon Crouse at Toledo, Ohio, 27 December 1957.

Lieutenant Schweibold flew the Sikorsky H-19B for the U.S.A.F. Air Rescue Service, assigned to Oxnard Air Force Base, California.

Air Rescue Service Sikorsky H-19A Chicasaw 51-3850. (AR.1999.026)

After leaving the Air Force, Jack flew Sikorsky S-55s for Chicago Helicopter Service, then Bell 47s for Butler Aviation. In 1960, he was hired by the Allison Division of General Motors as a test pilot and engineer for the new 250-series turboshaft engine.

A Chicago Helicopter Airways Sikorsky S-55.

Jack Schweibold is the author of In The Safety Of His Wings: A Test Pilot’s Adventure, published in 2005.

Jack was inducted into the Indiana Aviation Hall of Fame in 2022.

I have had the good fortune to know Jack Schweibold. I first met him through his involvement in the Helicopter Association International’s biennial flight instructor re-certification seminars, held during the HAI’s annual conventions. He kept the seminar classes on track, and in between, was always available for questions. Jack was the authority on Allison’s 250-series turboshaft engines, and over the years I have often called him for technical information and operational advice. On top of that, Jack Schweibold is just an all-around nice guy. It has been a pleasure to know him.

Jack Schweibold

© 2023, Bryan R. Swopes

14 April 1981

NASA JSC Electronic Imagery10:21 a.m., PST, 14 April 1981: The first space shuttle, Columbia, touches down on Runway 23, Edwards Air Force Base, California, completing the first space flight of the United States’ shuttle program.

With its two-man crew, commander, veteran astronaut John W. Young, and pilot Robert L. Crippen, Columbia traveled 1,074,567 miles (1,729,348 kilometers) on its 37-orbit journey, in 54 hours, 20 minutes, 53 seconds.

© 2016, Bryan R. Swopes

14 April 1953

Kamov Ka-15 first flight.

14 April 1953: Dmitry Konstantinovich Efremov, chief test pilot for the Kamov Design Bureau, made the first flight of the prototype Kamov Ka-15 helicopter.

The Ka-15 was a single-engine, two-place, light helicopter, flown by a single pilot. It used two fully-articulated, three-bladed, contra-rotating coaxial rotors. The helicopter had two vertical fins mounted at the ends of a horizontal stabilizer, and four-wheeled fixed landing gear.

The fuselage of the Ka-15 was 6.26 meters (20 feet, 6.5 inches) long. The main rotors’ diameter was 9.96 meters (32 feet, 8.1 inches), and the overall height of the the helicopter was 3.35 meters (10 feet, 11.9 inches). The span of the horizontal stabilizer and vertical fins were 2.85 meters (9 feet, 4.2 inches). The Ka-15 had an empty weight of 996 kilograms (2,196 pounds), normal takeoff weight of 1,360 kilograms (2,998 pounds), and maximum takeoff weight (MTOW) of 1,460 kilograms (3,219 pounds).

The rotors turn at 333 r.p.m. The upper rotor turned clockwise, as seen from above. (The advancing blade is on the left), and the lower blades turn counter-clockwise (their advancing blades are on the right). The area of the main rotor disc was 155.83 square meters (1,677.29 square feet) with a solidity ratio of 3% per rotor. (This is the lowest coefficient of disc area of any helicopter.) Each main rotor blade was trapezoidal, with a theoretical chord at the axis of rotation of 300 millimeters (11.8 inches), narrowing to 100 millimeters (3.9 inches) at the blade tip. The blades incorporated 12° of negative twist.

The Ka-15 was powered by a single air-cooled, supercharged 10.131 liter (618.234 cubic inches) Ivchenko AI-14V nine-cylinder radial engine with a compression ratio of 5.9:1. The engine was rated at 188 kilowatts (252 horsepower). It weighed approximately 200 kilograms (441 pounds).

The helicopter could carry a single passenger or 364 kilograms (802 pounds) of cargo. (Interestingly, the contemporary single main rotor/tail rotor Mil Mi-1 helicopter required 575 horsepower to lift the same payload as the Ka-15.)

The Ka-15 had a cruise speed 120 kilometers per hour (75 miles per hour) and maximum speed 155 kilometers per hour (96 miles per hour). The service ceiling was 3,500 meters (11,483 feet). It could hover out of ground effect (HOGE) at 600 meters (1,969 feet). The helicopter had a normal range of 278 kilometers (173 miles) and maximum range of 520 kilometers (323 miles).

The performance of the Ka-15 was better than had been predicted.  After several years of testing, the Ka-15 entered production in 1956. It was the first mass-produced coaxial helicopter, with approximately 375 being built by Aircraft Factory No. 99 at Ulan-Ude, the capitol city of the Buryat-Mongolian Autonomous Soviet Socialist Republic.

A Kamov Ka-15, circa 1953.
Nikolai Ilich Kamov

In a coaxial rotor system, one rotor is placed above the other, with the drive shaft for the upper rotor inside the hollow drive shaft of the lower. As in tandem rotor helicopters, each contra-rotating rotor counteracts the torque effect of the other. There is no anti-torque rotor (tail rotor) required. In helicopters using a tail rotor, as much as 30% of engine power is required to drive the tail rotor. With contra-rotating rotors, all of the engine’s power can be used to provide lift and thrust.

A second benefit of a coaxial rotor is that the dissymetry of lift of each rotor is also canceled out. There is no translating tendency while in a hover, and higher forward speeds are possible because the effect of retreating blade stall is reduced. A helicopter with coaxial rotors is more compact than a similar helicopter with tandem rotors. This makes it useful for operations in confined areas or aboard ships.

Nikolai Ilich Kamov was previously known for his autogyro designs, which were first produced in 1929. These included the Tsentralniy Aerogidrodinamicheskiy Institut (Central Aero-Hydrodynamic Institute) TsAGI A-7, which was the first armed autogyro. The Kamov Design Bureau was established 7 October 1948 at Lyubertsy, near Moscow, Russia.

The Kamov-designed TsAGI A-7 autogyro was armed with two 7.62 mm machine guns and could carry four 100 kilogram (220 pound) bombs or six RS-82 rockets under the fuselage.
Ефремов Дмитрий Константинович (Dmitry Konstantinovich Efremov).

Ефремов Дмитрий Константинович (Dmitry Konstantinovich Efremov) was born at Moscow, in the Russian Socialist Federative Soviet Republic, 30 October 1920.

In 1941, Efremov was a cadet at the Bauman Aero Club. He entered the Red Army the same year and was sent to the Saratov Military Aviation Gliding School, at Samara, Kuybyshev, Russia, U.S.S.R., for training as a military glider pilot. During the Great Patriotic War, Efremov flew gliders behind enemy lines. He was next assigned to an  experimental test squadron of of the Airborne Forces, and then as a pilot instructor at the aviation school of the Airborne Forces in Slavogorod, Altai Krai, Russia, U.S.S.R.

Efremov contracted tuberculosis and in January 1948, was discharged from the Red Army. He was employed as a senior technician at TsAGI, and in November of that year went to work as a mechanic at Kamov OKB. He made the first flight of the Kamov Ka-10, and was then sent to test pilot school.

D.K. Efremov with a float-equipped Kamov Ka-10M. (авиару.рф)

Efremov returned to Kamov OKB after completing test pilot school and was soon promoted the the design bureau’s chief pilot. He made the first flights of the Ka-15, Ka-18 and Ka-25 helicopters.

After transitioning to the Antonov An-8 and Ilyushin Il-18 turboprop transports to gain flight experience in larger transport airplanes, Efremov made the first flight of the Kamov Ka-22 gyrodyne prototype, 15 August 1959. On 7 October 1961, with V. V. Gromov, he flew the Ka-22 to a Fédération Aéronautique Internationale (FAI) World Record for Speed Over a 15km/25km Straight Course of 356.3 kilometers per hour (221.4 miles per hour),¹ and on 24 November 1961, set seven world records for payload to altitude.²

On 28 February 1962, Efremov and a flight test crew were conducting a long-distance test flight of a Kamov Ka-22M gyrodyne prototype, 01-01, 63972, from Tashkent, Uzbekistan, to Kzyl-Orda, Kazakhstan. During an intermediate refueling stop in Turkestan, mechanics found a loose or missing retaining nut for the left support of the synchronizing shaft. The problem was repaired and the flight continued.

While on approach to the main runway at the Dzhusaly airport, the gyrodyne suddenly banked left, entered a left spiraling turn, and, in an inverted dive, crashed on the runway. The Ka-22 exploded and burned. Dmitry Konstantinovich Efremov and seven men of his flight test crew were killed.

Kamov Ka-22 turboprop gyrodyne.

TDiA would like to thank regular reader Mike for suggesting this topic.

¹ FAI Record File Number 13226

² FAI Record File Numbers 13221, 13222, 13223, 13224, 13227 and 13228

© 2019, Bryan R. Swopes