Tag Archives: Prototype

18 June 1981

Lockheed Full Scale Development YF-117A, 79-10780, in light, three-tone desert camouflage. (Lockheed Martin)
Lockheed Full Scale Development YF-117A, 79-10780, in three-tone desert camouflage. (Lockheed Martin)

18 June 1981: At 6:05 a.m., Pacific Daylight Time (1305 UTC), the first Full Scale Development Lockheed YF-117A Nighthawk, 79-10780, made its first flight at Groom Lake, Nevada with Skunk Works test pilot Harold “Hal” Farley, Jr. at the controls. The super-secret airplane was made of materials that absorbed radar waves, and built with the surfaces angled so that radar signals are deflected away from the source.

Harold "Hal" Farley, Jr., with a Lockheed F-117A Nighthawk.
Harold “Hal” Farley, Jr., with a Lockheed F-117A Nighthawk. (Lockheed Martin)

Hal Farley is a former U.S. Naval Aviator who spent eight years testing F-14 Tomcat fighters for Grumman before going to work at Lockheed’s “Skunk Works.” He flew the Have Blue proof-of-concept prototype and the Senior Trend F-117 program. When he retired from Lockheed, Farley had more that 600 flight hours in the F-117s. His call sign is “Bandit 117.”

Commonly called the “Stealth Fighter,” the Nighthawk is actually a tactical bomber. Five developmental aircraft and 59 operational F-117As were built. They were in service from 1983 until 2008, when the Lockheed F-22 Raptor was planned to assume their mission. They are mothballed and could be returned to service if needed.

A Lockheed F-117A Nighthawk takes off from Groom Lake, Nevada.
A Lockheed F-117A Nighthawk takes off from Nellis Air Force, Base, Nevada. (Lockheed Martin)

The Lockheed F-117A Nighthawk is a single-seat, twin-engine tactical bomber with swept wings and tail surfaces. It is 65 feet, 11 inches (20.091 meters) long with a wingspan of 43 feet, 4 inches (13.208 meters) and height of 12 feet, 5 inches (3.785 meters). The wings’ leading edges are swept aft to 67° 30′. The total wing area is 912.7 square feet ( square meters). The Nighthawk has an empty weight of 29,500 pounds (13,381 kilograms) and a maximum takeoff weight of 52,500 pounds (23,814 kilograms).

The F-117 is powered by two General Electric F404-F1D2 engines. These are two-spool axial-flow turbofan engines which have a 3-stage fan section, 7-stage compressor and 2-stage turbine. They are rated at 10,540 pounds of thrust (46.88 kilonewtons), each. The -F1D2 is 2 feet, 10.8 inches (0.884 meters) in diameter, 7 feet, 3.0 inches (2.210 meters) long and weighs 1,730 pounds (785 kilograms).

The F-117A has a maximum speed of 0.92 Mach (608 miles per hour, 978 kilometers per hour) at 35,000 feet (10,668 meters). The service ceiling is 45,000 feet (13,716 meters) and range is 765 miles (1,231 kilometers), though inflight refueling capability gives it world-wide range.

F-117A drops GBU-28
A Lockheed F-117A Nighthawk drops a 2,000-pounds GBU-27 Paveway III laser-guided bomb. (U.S. Air Force)

The Nighthawk has no defensive armament. It can carry two 2,000 pound (907 kilogram) bombs in an internal bomb bay.

Lockheed built 5 YF-117As and 59 production F-117As. The F-117s were retired and placed in climate-controlled storage in 2008.

Scorpion One, 79-10780, is now mounted on a pylon as a “gate guard” at Nellis Air Force Base, Nevada.

Lockheed F-117A Nighthawk in flight. (U.S. Air Force)

© 2018, Bryan R. Swopes

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16 June 1943

Vega Aircraft Corporation XB-38 41-2401 (ex-Boeing B-17E Flying Fortress 41-2401), circa May–June 1943. (Lockheed Martin)

16 June 1943: The Boeing B-17E, F and G Flying Fortress heavy bomber was produced by a consortium of three aircraft manufacturers: Boeing in Seattle, Washington; the Douglas Aircraft Company at Long Beach, California; and the Vega Aircraft Corporation (a subsidiary of the Lockheed Aircraft Corporation) at Burbank, California. Exemplars of production B-17s were provided to Douglas and Vega.

The Flying Fortress that was sent to Vega was the ninth production B-17E, serial number 41-2401.

The U.S. Army Air Corps asked Vega convert 41-2401 by installing liquid-cooled Allison V-12 engines. By replacing the air-cooled Wright Cyclone R-1820-65 nine-cylinder radial engines it was hoped that more streamlined configuration would produce better performance in the same way as had modifying the Curtiss P-36 to the Allison-powered P-40.

Engine coolant radiators were placed in the leading edge of each wing between the inboard and outboard engines. The engines were the same variant as used for the starboard engine of the Lockheed P-38 Lightning.

Allison V-1710-89 V-12 installed on XB-38 41-2401. (Lockheed Martin)

The Vega XB-38 was powered by four liquid-cooled, turbosupercharged 1,710.597-cubic-inch displacement (28.032 liter) Allison Engineering Company V-1710-F-17R (V-1710-89) single overhead cam (SOHC) 60° V-12 engines. These had a continuous power rating of 1,100 horsepower at 2,600 r,p.m., to 30,000 feet (9,144 meters), and a takeoff/military power rating of 1,425 horsepower at 3,000 r.p.m. The engines drove three-bladed full-feathering constant-speed propellers through a 2.00:1 gear reduction. The engines were 7 feet, 1.34 inches (2.168 meters) long, 3 feet, 0.75 inches (0.933 meters) high, 2 feet, 5.28 inches (0.744 meters) wide, and weighed 1,350 pounds (612 kilograms).

The converted airplane was designated Vega XB-38. It made its first flight in the new configuration on 19 May 1943 with Vega’s Chief Pilot Bud Martin in the cockpit.

Vega XB-38 41-2401 (Lockheed Martin)

The XB-38 made its ninth test flight on 16 June 1943, with Bud Martin and former Naval Aviator George Archibald MacDonald on board. Flying over California’s San Joaquin Valley, the experimental bomber’s number three engine (inboard, starboard wing) caught fire.

When they were unable to extinguish the fire, Martin and MacDonald bailed out. MacDonald’s parachute failed to open and he was killed. Martin’s parachute opened improperly and he was severely injured when he hit the ground.

The Vega XB-38 crashed near Tipton, California, a small farming community on the valley floor, west of the Sierra Nevada Mountains. The bomber was destroyed.

Although the complete flight test program of the XB-38 was not completed, it was found that its performance increased only slightly over the B-17E. The project was cancelled.

Vega XB-38 41-2401 in flight, circa May–June 1943. (Lockheed Martin)

George Archibald MacDonald was born 7 August 1901 at Anaconda, Montana. He was the second son of Erwin H. MacDonald, a mining engineer, and Shuberta M. Swan MacDonald.

MacDonald served as an ensign in the United States Navy. In 1926, Ensign MacDonald was designated Naval Aviator #4331.

George Archibald MacDonald was buried at Forest Lawn Memorial Park, Glendale, California.

Bud Martin recovered from his injures and remained with Lockheed. On 3 December 1943, he took the PV-2 Harpoon for its first flight. He flew the first production C-130A Hercules at Marietta, Georgia, 7 April 1955.

© 2018, Bryan R. Swopes

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8 June 1966

XB-70A-2-NA Valkyrie 62-0207 leading a formation of aircraft powered by General Electric engines. Joe Walker’s F-104 is just below the B-70’s right wing tip. (U.S. Air Force)

8 June 1966: During a publicity photo formation flight, a Lockheed F-104N Starfighter, N813NA, flown by NASA Chief Research Test Pilot Joseph A. Walker, was caught in the wingtip vortices of the North American Aviation XB-70A-2 Valkyrie, 62-0207, the second prototype Mach 3+ strategic bomber. The Starfighter rolled up and across the Valkyrie. The two airplanes collided, with the F-104 taking off the Valkyrie’s vertical fins, then exploding.

Lockheed F-104N N813NA collided with North American Aviation XB-70A-2 Valkyrie 62-0207 and exploded, 8 June 1966. (U.S. Air Force)

The Valkyrie continued to fly straight and level for 16 seconds before it began to roll inverted. The B-70’s pilot, Alvin S. White, was able to eject, though he was severely injured. Joe Walker and B-70 co-pilot Major Carl S. Cross, United States Air Force, were killed.

The B-70 is out of control and going down in this photograph. Fuel is spraying out of damaged tanks. (U.S. Air Force)
The B-70 is out of control and going down in this photograph. A large section of the left wing is missing. JP-8 fuel is spraying out of damaged tanks. (U.S. Air Force)

Still photographs and motion picture film of the formation were being taken from Clay Lacy’s Gates Lear Jet. The photos were for a General Electric publicity campaign showing U.S. military aircraft that were powered by GE engines. Air Force procedures for requesting and approval of publicity flights were not properly followed and it is likely this flight would not have been approved had they been.

XB-70A-2 Valkyrie has rolled inverted and pitched nose down. (U.S. Air Force)
The XB-70A-2 Valkyrie has rolled inverted and pitched nose down. The outer section of the left wing is missing. The trailing edge and tip tank of the Lear Jet photo plane’s right wing are in the foreground. (U.S. Air Force)

Reportedly, just prior to the collision, Walker radioed, “I’m opposing this mission. It is too turbulent and it has no scientific value.”

The wreckage of the North American Aviation XB-70A-2 Valkyrie 62-0207 burnds on the desert floor, north of Barstow, california, 8 June 1968. (U.S. Air Force)
The wreckage of the North American Aviation XB-70A-2 Valkyrie 62-0207 burns on the desert floor at N. 35°03’47”, W. 117°01’27”, north of Barstow, California, 8 June 1966. (U.S. Air Force)

© 2016, Bryan R. Swopes

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1 June 1939

Focke-Wulf Fw 190 V1, D-OPZE, the first prototype. (Focke-Wulf Flugzeugbau AG)
Focke-Wulf Fw 190 V1, W.Nr. 0001, D-OPZE, the first prototype. (Focke-Wulf Flugzeugbau AG)

1 June 1939: At Bremen, Germany, Focke-Wulf Flugzeugbau AG chief test pilot Hans Sander took the first prototype of a new fighter, Fw 190 V1, W.Nr. 0001, registration D-OPZE, for its first flight.

Dipl. Ing. Hans Sander

The Fw 190 was designed as a fast, light-weight fighter with a powerful engine, easy to maintain under field conditions and able to absorb a reasonable amount of combat damage. The landing gear had a wide track which improved ground handling and was an advantage when operating on unimproved airfields. The mechanism used the gear’s own weight to lower it into place. Another interesting feature was to use of pushrods and bearings in place of the common cables and pulleys used to operate the flight controls. This gave a more precise, responsive operation. Also, the recent introduction of vacuum forming allowed a large one-piece “bubble” canopy to be used rather than the acrylic plastic/metal framework which was used in other fighters, such as the Messerschmitt Bf 109.

V-1 near completion.
The prototype Focke-Wulf Fw 190 V1 W.Nr. 0001. (Focke-Wulf Flugzeugbau AG)

Focke-Wulf frequently named its airplanes after birds. The Fw 190 was known as the Würger, or Shrike.

Fw 190 V1 (Versuchsflugzeug 1) was 8.730 meters (28 feet, 7¾ inches) long with a wingspan of 9.500 meters (31 feet, 2 inches). It weighed approximately 3,000 kilograms (6,615 pounds).

Focke-Wulf Fw 190 V1, D-OPZE, the first prototype. (Focke-Wulf Flugzeugbau AG)
Focke-Wulf Fw 190 V1, D-OPZE, the first prototype, during flight. The long landing gear struts were made necessary by the use of a large diameter propeller. (Focke-Wulf Flugzeugbau AG)

D-OPZE was powered by an experimental air-cooled, supercharged 55.4-liter (3,380.4 cubic inch) BMW 139 two-row, 18-cylinder, radial engine which produced 1,529 horsepower. This engine had been developed from the nine-cylinder Pratt & Whitney Hornet (R-1690) which Bayerische Motoren Werke AG (BMW) built under license. (A redesign of the BMW 139 engine resulted in the 14-cylinder BMW 801 which was used in the production Fw 190.)

The propeller was a three-bladed Vereingite Deutsche Metallwerke (VDM) variable-pitch unit with a diameter of 3.460 meters (11 feet, 4¼ inches). It was driven at 54% of engine speed through a gear reduction unit.

To minimize aerodynamic drag, the large radial engine was tightly cowled and a large propeller spinner used. Cooling air entered through an opening at the center of the spinner and a fan between the propeller and the front of the engine circulated air. This was unsatisfactory and was significantly changed with the second prototype.

Focke-Wulf Fw 190 V1 W.Nr. 0001, D-OPZE. (Focke-Wulf Flugzeugbau AG)

After testing by Focke-Wulf at Bremen, Fw 190 V1 was flown to the Luftwaffe test site at Rechlin-Lärz Airfield. Its identification markings were changed to FO+LY. Later, they were changed again, to RM+CA. V1 continued to be used for testing until 29 March 1943.

Fw 190 V1 after the original spinner was replaced. The cooling fan behind the propeller is visible. The prototype is now marked FO+LY. (Focke-Wulf Flugzeugbau AG)
Focke-Wulf Fw 190 V1 W.Nr. 0001 with modified engine cowling. The prototype is now camouflaged and marked with the Luftwaffe Balkenkruz and the swastika of the Deutsches Reich. The identification marks have been changed to  FO+LY. (Focke-Wulf Flugzeugbau AG)

The Fw 190 was the most effective of Germany’s world War II fighters. More than 20,000 were built in 16 variants. The Focke-Wulf factory at Marienburg and the AGO Flugzeugwerke at Oschersleben were frequently attacked by Allied bombers.

A captured Focke-Wulf Fw 190 in flight. (U.S. Air Force)
A captured Focke-Wulf Fw 190 G-3 DN+FP, W.Nr. 160016, in flight near Wright Field, Ohio, 26 May 1944. (U.S. Air Force)

A Focke-Wulf Fw 190 G-3 fighter bomber, W.Nr. 160016, which had been captured in Italy, was flight tested by the U.S. Army Air Force at Wright Field, Ohio, from 25 March to 15 April 1944, flown by Major Gustav Edward Lundquist, U.S. Army Air Force. In a report dated 26 May 1944, it was described as having a length of 29.1 feet (8.87 meters) and wingspan of 34.5 feet (10.52 meters), and was tested with maximum gross weight of 8,535 pounds (3,871 kilograms).

This aircraft was powered by an air-cooled, supercharged and fuel-injected 41.744 liter (2,547.4 cubic inch) BMW 801-D two-row, fourteen-cylinder radial engine which produced 1,750 horsepower at 2,700 r.p.m. with 41.1 inches of manifold pressure (1.39 bar). It could climb at 4,000 feet per minute (20.32 meters per second) and reach 20,000 feet (6,096 meters) in 7.3 minutes. 160016 had a maximum airspeed of 415 miles per hour (668 kilometers per hour) at 22,000 feet (6,706 meters). The service ceiling was 36,100 feet (11,003 meters).

The fighter was described to have performance “definitely weaker than standard AAF fighters at altitudes above 28,000 feet.”  [8,534 meters]

The Fw 190 G-3 was armed with two Waffenfabrik Mauser AG MG151/20 20 mm autocannon with 550 rounds of ammunition.

Focke-Wulf Fw 190 G-3 DN+FP, W.Nr. 160016, in flight near Wright Field, Ohio, May 1946. (U.S. Air Force)

(Two months later, Major Lundquist was in Europe, flying with the 486th Fighter Squadron, 352nd Fighter Group. On 29 July 1944, his North American Aviation P-51D-5-NA Mustang, 44-13395, was shot down by a Messerschmiit Bf 109 G-6 near Merseberg, Germany. Lundquist was captured and remained a Prisoner of War until the end of World War II. He was officially credited with 2 enemy aircraft destroyed. After the war, he returned to Wright Field and flight test. On 2 September 1946, Major Lundquist won the Thompson Trophy Race (J Division) while flying a Lockheed P-80A Shooting Star. Remaining in the Air Force for 29 years, he rose to the rank of brigadier general.)

Focke-Wulf-Fw-190-WNr-50046-in-flight-01
Focke-Wulf Fw 190 G-3 DN+FP, W.Nr. 160016, from above and behind. (U.S. Air Force)

© 2018, Bryan R. Swopes

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30 May 1958

Douglas DC-8-11 N8008D takes of from Long Beach Airport, 10:10 a.m., 30 May 1958.
Douglas DC-8-11 N8008D takes of from Long Beach Airport, 10:10 a.m., 30 May 1958. The heavy dark exhaust smoke is a result of water injection. (Los Angeles Public Library)

30 May 1958: Douglas Aircraft Company Flight Operations Manager and engineering test pilot Arnold G. Heimerdinger, with co-pilot William M. Magruder and systems engineer Paul H. Patten, were scheduled to take off from Long Beach Airport (LGB) on the coast of southern California, at 10:00 a.m., to make the first flight of the new Douglas DC-8 jet airliner, c/n 45252, FAA registration N8008D.

Crowds of spectators, estimated as many as 50,000 people, were surrounding the airport. For this first test flight, the Federal Aviation Administration required a minimum of five miles visibility. Typical Southern California coastal low clouds and fog caused a ten minute delay.

Taking off at 10:10 a.m., N8008D climbed out to the south over the Pacific Ocean. Escorted by a company-owned Douglas DC-7 engineering and photo plane and a Lockheed T-33A Shooting Star chase, the DC-8 climbed to 11,000 feet (3,353 meters) and went through a series of pre-planned flight maneuvers and systems checks. Heimerdinger took the airliner north to Edwards Air Force Base in the high desert of southern California, where the full flight test program would be carried out. The total duration of the first flight was 2 hours, 10 minutes.

In an article written the following year, Heimerdinger said that the DC-8 was easy to fly and never presented any difficulties during the test program.

Douglas DC-8 N8008D accompanied by a Cessna T-37. (Douglas Aircraft Company)
Douglas DC-8 N8008D accompanied by a U.S. Air Force Cessna T-37 chase plane during a test flight near Edwards Air Force Base, California. (Douglas Aircraft Company)

The Douglas DC-8 Jetliner is a commercial airliner, a contemporary of the Boeing 707 and Convair 880. It was operated by a flight crew of three and could carry up to 177 passengers. It was powered by four turbojet engines mounted on pylons suspended below the wings. The wings’ leading edges were swept to 30° as were the vertical fin and horizontal tailplane. The airplane is 150 feet, 6 inches (45.872 meters) long with a wingspan of 142 feet, 5 inches (43.409 meters) and overall height of 42 feet, 4 inches (12.903 meters). N8008D was a Series 10 version. It had an empty weight of 119,767 pounds (54,325 kilograms) and maximum takeoff weight of 273,000 pounds (123,831 kilograms).

N8008D was originally powered by four Pratt & Whitney JT3C-6 turbojet engines, the same engines which powered its Boeing rival. It is a two-spool, axial-flow turbojet engine with a 16-stage compressor and 2-stage turbine. The JT3C-6 was rated at 11,200 pounds of thrust (49.82 kilonewtons), and 13,500 pounds (60.05 kilonewtons) with water/methanol injection). The JT3C is 11 feet, 6.6 inches (3.520 meters) long, 3 feet, 2.9 inches (0.988 meters) in diameter, and weighs 4,235 pounds (1,921 kilograms). The engines were later upgraded to JT3D-1 turbofan engines which produced 17,000 pounds of thrust.

The DC-8-10 series had a cruising speed of 0.82 Mach (542 miles per hour/872 kilometers per hour) at 35,000 feet (10,668 meters). Its maximum range was 5,092 miles (8,195 kilometers).

On 21 August 1961, a Douglas DC-8-43, N9604Z, c/n 45623, Line Number 130, flown by Chief Test Pilot William Magruder, Paul Patten, Joseph Tomich and Richard Edwards, climbed to 50,090 feet (15,267 meters) near Edwards Air Force Base. Magruder put the DC-8 into a dive, and the airplane reached Mach 1.012 (668 miles per hour/1,075 kilometers per hour) while descending through 41,088 feet (12,524 meters). The airliner maintained this supersonic speed for 16 seconds.

This was the first time that a civil airliner had “broken the Sound Barrier.” An Air Force F-100 Super Sabre and F-104 Starfighter were chase planes for this flight. Reportedly, the F-104 was flown by the legendary test pilot, Colonel Chuck Yeager.

Douglas DC-8-43 N9604Z is accopmanied by a U.S. Air Force Lockheed F-104A Starfighter, near Edwards Air Force base, California.
Douglas DC-8-43 N9604Z, in Canadian Pacific livery, is accompanied by a U.S. Air Force Lockheed F-104A-10-LO Starfighter, 56-0749, near Edwards Air Force Base, California. The dark sky suggests that the airplanes are at a very high altitude. (Unattributed)

N9604Z was powered by four Rolls-Royce Conway RCo.12 Mk 509 two-shaft axial-flow turbofan engines, rated at 17,500 pounds of thrust (77.844 kilonewtons) at 9,990 r.p.m. The 509 is 11 feet, 3.9 inches (3.452 meters) long, 3 feet, 6.2 inches (1.072 meters) in diameter, and weighs 4,542 pounds (2,060 kilograms).

N9604Z was delivered to Canadian Pacific Airlines, 15 November 1961, registered CF-CPG, and named Empress of Montreal. It later flew under CP Air as Empress of Buenos Aires. It was scrapped at Opa Locka Municipal Airport, north of Miami, Florida, in May 1981.

In 1960, N8008D was converted to the DC-8-51 configuration. With a change to the more powerful JT3D-1 turbofan engines, the airliners maximum takeoff weight was increased to 276,000 pounds (125,191 kilograms).

After the flight test and commercial certification program was completed, on 21 June 1961, Douglas leased N8008D to National Airlines, based at Miami, Florida. One year later, 20 June 1961, it was sold to Trans International Airlines. TIA leased the DC-8 to Lufthansa, 11 May 1965, and to Canadian Pacific, 1 October 1966. It was re-registered CF-CPN and named Empress of Santiago.

Douglas DC-8-51 N8008D, owned by Trans International Airways, was photographed at London Gatwick Airport, 23 July 1966. (RuthAS)
Douglas DC-8-51 N8008D, owned by Trans International Airways, was photographed at London Gatwick Airport, 23 July 1966. (RuthAS)

TIA sold the DC-8 to Delta Airlines, Atlanta, Georgia, 1 October 1967. It reverted to its FAA-assigned registration, N8008D. Delta gave it fleet number 800.

In March 1979, Delta sold N8008D to F.B. Myers and Associates. On 1 April, F.B. Myers leased the it to Aerovias de México, S.A. de C.V. (Aeroméxico). The DC-8 was assigned Mexican registration XA-DOE and named Quintana Roo.

The first Douglas DC-8 was placed in storage at Marana-Pinal Airpark, north of Tucson, Arizona, 7 January 1982. In May 1989, it was sold to Agro Air, a Caribbean regional cargo airline. It remained at Marana and was used as a source of parts. In 2001, c/n 45252 it was scrapped.

Between 1959 and 1972, Douglas produced 556 DC-8s in passenger and freighter configurations.

A.G. Heimerdinger
Arnold George Heimerdinger, Flight Operations Manager, Douglas Aircraft Company. (Photograph courtesy of Neil Corbett, Test and Research Pilots, Flight Test Engineers)

Arnold George Heimerdinger was born in Manchester Township, Michigan, 7 December 1910. His parents were Charles and Minnie L. Uphaus Heimerdinger. He studied electrical engineering at the University of Michigan. Heimerdinger married Miss Mary Aileen Eggert 19 August 1935.

A.G. Heimerdinger was commissioned as an ensign in the United States Navy, 27 November 1942 and served as a Naval Aviator until he was released from active duty, 14 October 1945.

Heimerdinger worked as an engineering test pilot for the Federal Aviation Administration, and he flew certification tests of the Boeing 377 Stratocruiser, Convair 240 and 340 Metroliner, and the Lockheed L-640 and L-1049 Constellation.

He joined the Douglas Aircraft Company at Santa Monica, California, in 1952 and remained with the company until he retired in 1974. He was the project test pilot for the Douglas DC-6B and the DC-7. Transferring to Douglas’ Long Beach Division, a few miles southeast, he was project test pilot for the DC-8 and DC-9 jet airliners.

Arnold G. “Heimie” Heimerdinger died at Santa Monica, California, 17 July 1975.

© 2018, Bryan R. Swopes

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