15 August 1939

Junkers Ju 87 B-1 Sturzkampfflugzeug (“Stuka”) photographed before World War II.

15 August 1939: As Nazi Germany prepared for a war now just weeks away, the Luftwaffe gave a demonstration of its Junkers Ju 87 B-1 Stuka dive bombers for a group of generals at a test range near Neuhammer-am-Queis, Silesia :

“. . . scores of generals were assembled at the training area at Neuhammer to watch a dive-bombing demonstration. Already, said Rudolf Braun, who took part with his unit (I St. G 3) there was a feeling of war in the air.

Hauptmann Rudolf Braun, Knight’s Cross of the Iron Cross

“Normally the order of attack was the Kommandeur’s Stab Kette (Staff Flight) first, followed by Staffels 1, 2, and 3. For some unknown reason Staffel I, led by Oberleutnant Peltz, was this time ordered to attack last. It would save Rudolf Braun’s life.

“The Met. reported cloud from 6,000 feet down to 2,500 with clear visibility below. At 6.00 a.m. Hauptmann Sigel led his Gruppe into attack at 12,000 feet. Half-rolling his Ju. 87 he plunged nearly vertically earthwards, with Oberleutnants Eppen and Mueller on each side.

“On the ground below, the generals (including Wolfram von Richthofen, the Stuka’s chief) listened to the whining crescendo of the dive-bombers as they plummeted towards the ground. Horrified, they knew that nothing could avert disaster. The Met. report was wrong. Cloud base was at three hundred feet.

Hauptmann Sigel, yelling into his microphone, “Pull out!” managed to do so himself a few feet above the trees. But Eppen went in, Mueller went in, and both burst into flames. The nine Ju. 87s of Staffel 2 and two of Staffel 3 all went in.

“Rudolf Braun and his comrades of Staffel I had heard Sigel’s warning and remained circling above the cloud layer through which columns of black smoke were now rising from the wreckage of thirteen dive bombers. I St. G 3 lost twenty-six young aircrew that day.”

— Duel of Eagles, Group Captain Peter Wooldridge Townsend, C.V.O., D.S.O., D.F.C. and Bar, Royal Air Force. Castle Books, Edison, New Jersey, 2003, Chapter 14 at Pages 171–172.

Two Junkers Ju 87 Stuka dive bombers.

The Junkers Flugzeug-und-Motorenwerke AG Ju 87 B-1 Sturzkampfflugzeug (“diving combat aircraft”) was a two-place, single-engine, low-wing monoplane with fixed landing gear, designed as a dive bomber. The airplane, commonly known as the “Stuka,” has a blocky, unstreamlined appearance. Its most identifiable feature is its sharply-tapered, inverted “gull wing.” ¹

The Ju 87 made its first flight 17 September 1935. Among the tests pilots who flew it during pre-production testing were Hanna Reitsch and aeronautical engineer Gräfin Melitta Schenk von Stauffenberg.

The Stuka was used in the murderous attacks on the Spanish market town of Guernica, 26 April 1937, and Wieluń, Poland, 1 September 1939.

The Ju 87 B-1 was the first variant to be produced in large numbers and was in service at the beginning of World War II. The airplane is 11.000 meters (36.089 feet) long with a wingspan of 13.800 meters (45.276 feet) and height of 3.770 meters (12.369 feet). The total wing area is 31.9 square meters (343.4 square feet). The B-1 variant had an empty weight of 2,745 kilograms (6,052 pounds), and gross weight of 4,235 kilograms (9,337 pounds).

Two-view illustration of the Junkers Ju 87 B-1, with dimensions in millimeters. (Junkers Ju 87 B-1 Betriebsanleitung, at Page 0 05)

The Ju 87 B-1 was powered by a liquid-cooled, supercharged 34.989 liter (2,135.190 cubic-inch-displacement Junkers Jumo 211 A inverted 60° V-12 engine. The 211 A had direct fuel-injected and the cylinder heads were machine for four spark plugs per cylinder. The compression ratio was 6.57:1, requiring 88-octane gasoline. It was rated at a maximum 900 Pferdestärke at 2,200 r.p.m. at 5,500 meters (18,045 feet). The engine turned a three-blade Junkers-Verstelluftschraube propeller with a diameter of 3.4 meters (11.2 feet) through a 1.55:1 gear reduction. The Jumo 211 A weighed 660 kilograms (1,455 pounds).

The Stuka B-1 had a maximum dive speed of 600 kilometers per hour (373 miles per hour). The Ju 87 B-1 had a service ceiling of 8,000 meters (26,247 feet), and range of 550 kilometers (342 miles).

The B-1 was armed with two fixed 7.92 mm Rheinmetall-Borsig MG17 w/ 1,000 rpg, and one MG 15 flexible w/ 900 rpg. It could carry a single 500 kilogram (1,102 pound) bomb under the fuselage.

An intersting feature the the Stuka was its automatic pull-out system. Once the bomb had been dropped, the airplane automatically began a 5–6 g recovery. This could save the airplane if the pilot became target-fixated, or blacked out.

The Ju 87 was equipped with a Zeiss gyro-stabilized bomb sight. According to an article in Air Force Times, the Stuka was a very accurate dive bomber. “. . . even the worst drops typically landed within 100 feet [30.5 meters] of the target. Good hits were either on target or no more than 15 feet [4.6 meters] off-center.”

In the same article, the legendary Royal Navy test pilot, Captain Eric Melrose Brown, C.B.E., D.S.C., A.F.C., K.C.V.S.A., Ph.D., Hon. F.R.Ae.S., R.N., is quoted:

A dive angle of 90 degrees is a pretty palpitating experience, for it always feels as if the aircraft is over the vertical and is bunting, and all this while terra firma is rushing closer with apparent suicidal rapidity. In fact I have rarely seen a specialist dive bomber put over 70 degrees in a dive, but the Ju 87 was a genuine 90-degree screamer. . . the Ju 87 felt right standing on its nose, and the acceleration to 335 mph [539 km/h] was reached in about 4,500 feet [1,372 meters], speed thereafter creeping up to the absolute permitted limit of 375 mph [604 km/h], so that the feeling of being on a runaway roller coaster experienced with most dive bombers was missing. I must confess that I had a more enjoyable hour’s dive-bombing practice than I had ever experienced with any other aircraft of this specialist type. Somehow the Ju 87D did not appear to find its natural element until it was diving steeply. Obviously the fixed undercarriage and large-span dive brakes of the Junkers were a highly effective drag combination.”

Only two Stukas still exist, one at the RAF Museum at Hendon, and the other at the Chicago Museum of Industry.

¹ TDiA has not found any source that provides the details of the Ju 87’s most characteristic feature: the angles of anhedral and dihedral of its wings. TDiA estimates that the wings’ inner section has -12° anhedral, while the outer wing panels have approximately 8° dihedral.

© 2018, Bryan R. Swopes

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15 August 1935

Will Rogers and Wiley Post with the Lockheed Model 9E Orion hybrid at Renton, Washington. The pontoons have just been installed on the airplane in place of its fixed landing gear. (Unattributed)
Will Rogers and Wiley Post with the Lockheed Model 9E Orion hybrid at Renton, Washington. The pontoons have just been installed on the airplane in place of its fixed landing gear. (Seattle Post Intelligencer Collection/Museum of History & Industry)

15 August 1935: Two of the most famous men of their time, Wiley Hardeman Post and William Penn Adair (“Will”) Rogers, were killed in an airplane crash near Point Barrow, Alaska.

Post, a pioneering aviator who had twice flown around the world—once, solo—and helped develop the pressure suit for high altitude flight, was exploring a possible air mail route from the United States to Russia. His friend, world famous humorist Will Rogers, was along for the trip.

Transcontinental and Western Airlines' Lockheed Model 9E special, NC12283. This airplane would be modified by Pacific Airmotive, Burbank, California, for Wiley Hardeman post. (Ed Coates Collection)
Transcontinental & Western Air Incorporated’s Lockheed Model 9E Special, NC12283. This airplane would be modified by Pacific Airmotive, Burbank, California, for Wiley Hardeman Post. (Ed Coates Collection)

Post’s airplane was a hybrid, built from the fuselage of a former Transcontinental & Western Air, Inc., Lockheed Model 9E Orion Special, NC12283, combined with a wing from a Lockheed Model 7 Explorer. T&WA operated the Orion for two years before selling it to Charles Babb, Glendale, California. Babb installed the salvaged wing from a modified Lockheed Model 7 Explorer, Blue Flash, NR101W, which had crashed in Panama in 1930.

The Orion’s standard 450 horsepower Pratt & Whitney Wasp SC1 engine was replaced with an air-cooled, supercharged, 1,343.8-cubic-inch-displacement (22.021 liter) Pratt & Whitney Wasp S3H1 nine-cylinder radial engine (serial number 5778), rated at 550 horsepower at 2,200 r.p.m. to 5,000 feet (1,524 meters), and 600 horsepower at 2,250 r.p.m. for takeoff. A three-bladed Hamilton Standard variable-pitch propeller was used. Both the SC1 and S3H1 were direct drive engines. The S3H1 was 3 feet, 7.01 inches (1.093 meters) long and 4 feet, 3.60 inches (1.311 meters) in diameter. It weighed 865 pounds (392 kilograms).

Post also wanted to replace the retractable landing gear with pontoons for water landings.

Lockheed engineers were of the opinion that the hybrid aircraft and the other modifications which were requested by Post were dangerous and refused to do the work. Pacific Airmotive, also located in Burbank, California, however, agreed to modify the airplane. Several names were used to describe the hybrid airplane, such as “Lockheed Aurora,” as well as others perhaps less polite. It was given the restricted registration NR12283.

NR12283 was 27 feet, 6 inches (8.382 meters) long with a wingspan of 48 feet, 6 inches (14.783 meters). The wing area was 313 square feet (29.079 square meters).

Wiley Post’s red Lockheed Orion/Explorer hybrid, NR12283, at Renton, Washington.

Post had the pontoons installed at Renton, Washington. The floats that he had ordered did not arrive on time so he installed a larger set intended for another aircraft.

NR12283, Wiley Post's hybrid Lockheed Orion/Explorer float plane, at Fairbanks, Alaska. (PBS)
NR12283, Wiley Post’s red hybrid Lockheed Orion/Explorer float plane, at Fairbanks, Alaska. (PBS)

After several days of flying from Seattle and through Alaska, Post and Rogers were nearing Point Barrow on the northern coast of the continent. They encountered dense fog and landed on Walakpa Bay, about 13 miles (21 kilometers) southwest of the village of Barrow.

“August 15, 1935 2:00 p.m. — Harding Lake, Alaska. Wiley Post and Will Rogers taxi for take-off. Last photo before their 6:30 p.m. crash near Barrow. Patton Collection #13 ” (Harding Lake Association)

After talking with a local resident, Clair Okpheah, they taxied back on the lagoon and took off to the north. Post banked to the right, but at about 50 feet (15 meters) the engine stopped. NR12283 pitched down, rolled to the right, and then its right wing struck the mud. The right wing and pontoon were torn off and the airplane crashed upside down. Post and Rogers died.

Clair Okpheah ran to Barrow for help. When a rescue party arrived 16 hours after the crash, the men recovered the bodies of Post and Rogers. It was noted that Wiley Post’s wristwatch had stopped at 8:18 p.m.

Wiley Post's hybrid airplane, NR12283, after the crash, 15 August 1935. (UPI)
The wreckage of Wiley Post’s Lockheed Model 9E Orion hybrid airplane, NR12283, after the crash at Walakpa Lagoon, Alaska, 15 August 1935. (UPI)

© 2018, Bryan R. Swopes

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14 August 1979

Red Baron, an Unlimited Class RB51 Mustang. (Octane 130)
Red Baron, an Unlimited Class RB51. (Octane 130)

14 August 1979: Air racer Steve Hinton set a new Fédération Aéronautique Internationale (FAI) speed record for piston engine, propeller-driven airplanes when he flew his highly-modified North American Aviation P-51 Mustang, Red Baron, to an average 803.138 kilometers per hour (499.047 miles per hour) over a 3 kilometer course at Tonapah, Nevada.¹

Unlimited Class North American Aviation P-51 Mustang, Red Baron.
Unlimited Class North American Aviation P-51 Mustang, Red Baron. (Jon R. Wallace)
Steve Hinton

Steve Hinton’s Mustang was a Dallas, Texas-built North American Aviation P-51D-25-NT, serial number 44-84961. His company, Fighter Rebuilders, modified the airplane for racing. The most noticeable change is the substitution of the standard Packard V-1650-7 Merlin V-12 engine and its four-bladed propeller with a larger, more powerful, 2,239.33-cubic-inch-displacement (36.695 liter) liquid-cooled, supercharged Rolls-Royce Griffon 57 single overhead cam (SOHC) 60° V-12 engine and dual, three-bladed, counter-rotating propellers from an Avro Shackleton bomber. A revised engine cowling gave Red Baron an appearance similar to the Allison-powered XP-51.

Red Baron crashed 16 September 1979 when an oil pump failure caused the propeller blades to move to flat pitch, dramatically increasing aerodynamic drag. Hinton suffered serious injuries but survived.

¹ FAI Record File Number 8438

© 2017, Bryan R. Swopes

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14 August 1968

Sikorsky S-61L N300Y, Los Angeles Airways, at Disneyland Heliport, Anaheim, California. (Robert Boser)
Sikorsky S-61L N300Y, Los Angeles Airways, at Disneyland Heliport, Anaheim, California. (Robert Boser)

14 August 1968: At 10:28:15 a.m., Pacific Daylight Time, Los Angeles Airways Flight 417, a Sikorsky S-61L helicopter, departed Los Angles International Airport (LAX) on a regularly-scheduled passenger flight to Disneyland, Anaheim, California. On board were a crew of three and eighteen passengers. The aircraft commander, Captain Kenneth L. Waggoner, held an Airline Transport Pilot certificate and was type-rated in the Sikorsky S-55, S-58 and S-61L. He had a total of 5,877:23 flight hours, with 4,300:27 hours in the S-61L. Co-pilot F. Charles Fracker, Jr. had 1,661:18 flight hours, of which 634:18 were in the S-61L. Flight Attendant James A. Black had been employed with LAA for nearly ten years.

At approximately 10:35 a.m., while flying at an estimated altitude of 1,200–1,500 feet (370–460 meters) above the ground, one of the helicopter’s five main rotor blades separated from the aircraft which immediately went out of control, started to break up, and crashed in a recreational park in Compton. All twenty-one persons on board, including the 13-year-old grandson of the airlines’ founder and CEO, were killed.

The Sikorsky S-61 was registered N300Y.  It had been the prototype S-61L, serial number 61031. Los Angeles Airways was the first civil operator of the S-61, purchasing them at a cost of $650,000 each. As of the morning of 14 August 1968, 61031 had accumulated a total of 11,863.64 hours flight time on the airframe (TTAF). It flew an estimated 3.17 hours on the morning of the accident.

The Sikorsky S-61L was a civil variant of the United States Navy HSS-2 Sea King, and was the first helicopter specifically built for airline use. The prototype, N300Y, first flew 2 November 1961. It is a large twin-engine helicopter with a single main rotor/tail rotor configuration. Although HSS-2 fuselage is designed to allow landing on water, the S-61L is not amphibious, having standard fixed landing gear rather than the sponsons of the HSS-2 (and civil S-61N). The S-61L fuselage is 4 feet, 2 inches (1.270 meters) longer than that of the HSS-2. The S-61L is 72 feet, 7 inches (22.123 meters) long and 16 feet, 10 inches (5.131 meters) high, with rotors turning.

The main rotor has five blades and a diameter of 62 feet (18.898 meters). Each blade has a chord of 1 foot, 6.25 inches (0.464 meters). The tail rotor also has five blades and a diameter of 10 feet, 4 inches (3.149 meters). They each have a chord of 7–11/32 inches (0.187 meters). At 100% r.p.m., the main rotor turns 203 r.p.m. and the tail rotor, 1,244 r.p.m. The main rotor turns counter-clockwise, as seen from above. (The advancing blade is on the helicopter’s right side.) The tail rotor turns clockwise, as seen from the left side. (The advancing blade is below.)

The S-61L was powered by two General Electric CT58-140-1 turboshaft engines, each of which was rated for 1,400 shaft horsepower for takeoff and maximum power of 1,500 shaft horsepower for 2½ minutes. The main transmission was rated for 2,300 horsepower, maximum.

The S-61 has a cruise speed of  166 miles per hour (267 kilometers per hour).  The service ceiling is 12,500 feet (3,810 meters). 61031 had a maximum takeoff weight (MTOW) of 19,000 pounds (8,618.3 kilograms).

Between 1958 and 1980, Sikorsky built 794 S-61 series helicopters. 13 were S-61Ls.

The National Transportation Safety Board investigation found that most of the helicopter was contained with a small area of Leuders Park. One main rotor blade, however, was located approximately 0.25 miles (0.40 kilometers) west of the main wreckage. This blade is referred to as the “yellow” blade. (The main rotor blades marked with colored paint for simplicity, red, black, white, yellow, and blue.) Analysis found that this blade’s spindle, where it attached to the main rotor hub assembly, had failed due to a fatigue fracture. It was believed that the fracture began in an area of substandard hardness which was present in the original ingot from which the part was forged, and that inadequate shot-peening of the part during the overhaul process further weakened the spindle.

Diagram of fractured main rotor spindle. (NTSB)
Diagram of fractured main rotor spindle. (NTSB)

Los Angeles Airways had experienced a similar accident only three months earlier which had resulted in the deaths of all 23 persons on board. (Flight 841, 22 May 1968). L.A. Airways never recovered from these accidents and ceased all operations by 1971.

© 2016, Bryan R. Swopes

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14 August 1953

Commonwealth Aircraft Corporation CA-26 Sabre A94-101 (Royal Australian Air Force)

14 August 1953: Near Avalon Field, Geelong, Victoria, Australia, Flight Lieutenant William H. Scott, Royal Australian Air Force, the 28-year-old Chief Test Pilot of the Government Aircraft Factories, put the new Commonwealth Aircraft Corporation, Pty. Ltd., prototype into shallow dive from 25,000 feet (7,620 meters) over Port Phillip Bay. This was the new airplane’s sixth test flight. Scott passed 670 miles per hour (1,078 kilometers per hour) and broke the “sound barrier.” A triple sonic boom was heard throughout the Melbourne area.

The aircraft was the CA-26 Sabre, A94-101. The Australian-built Sabre had made its first flight 1 August, also with Flt. Lt. Scott in the cockpit. After about a week there were reports of sonic booms in the area around Melbourne.

CAC Sabre A94-101
Commonwealth Aircraft Corporation CA-26 Sabre A94-101 (Royal Australian Air Force)

Based on the highly successful North American Aviation F-86F Sabre, the C.A.C. variant used a license-built Rolls-Royce Avon RA.7 turbojet with 7,350 pounds of thrust. The Sabre’s fuselage had to be extensively redesigned to allow installation of the new engine. Although it was about the same size as the J47 it replaced, the Avon needed a much larger intake duct. And because it weighed less than the J47, it had to be moved aft to maintain the Sabre’s center of gravity. Only about 40% of the original structure remained.

Other changes were replacing the fighter’s basic armament of six .50-caliber Browning machine guns with two 30 mm ADEN revolver cannon. In testing, it was found that teh muzzle blast of the ADEN cannons could cause the engine to flame out. “Maxim” shock wave baffles were installed to eliminate the problem.

Commonwealth Aircraft Corporation CA-26 Sabre A94-901. (Royal Australian Air Force)

The aircraft, often called the “Avon Sabre,” was put into production as the CA-27 Sabre Mk 30. Twenty-two aircraft were built in the version. With the introduction of the Mark 31, the original Sabres were upgraded to the new standard. Sixty-nine Sabre Mk 32 fighters were built with the Avon 25 engine and increased fuel capacity.

The CA-27 was in service with the Royal Australian Service from 1954 until 1971. Several were transferred to Malaysia and Indonesia and operated for those countries until 1982.

CAC CA-27 Sabre Mk 32 A94-901
Commonwealth Aircraft Corporation CA-27 Sabre Mk 32 A94-901 (RAAF)

The prototype CA-26 Sabre, A94-901, flew with several RAAF squadrons, including the 76 Squadron “Black Panthers” Aerobatic Team, 1961–1965. It was withdrawn from service in 1966. The Sabre was restored by Hawker de Havilland at Bankstown Airport, before being sent to the Historical Aircraft Restoration Society Museum (“HARS”) at Illawarra Regional Airport, south of Sydney, New South Wales, Australia. The airplane is again in the livery of the “Black Panthers.”

A94-901 ias it appeared when assigned to 76 Squadron “Black Panthers,” 1961–1965. (HARS Museum)

© 2018, Bryan R. Swopes

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