Welcome to This Date in Aviation History, getting of you caught up on milestones, important historical events and people in aviation from October 21 through October 24.
October 21, 1947 – The first flight of the Northrop YB-49. In fixed-wing aircraft, it is the wings that generate the lift required to fly. But all the other parts of the aircraft, particularly the fuselage, while necessary for crew and cargo, provide little to no lift, produce aerodynamic drag and add extra weight. So, in order to create an aircraft that is almost entirely lift, why not remove the entire fuselage and just fly the wing by itself? That was the question that Jack Northrop doggedly pursued throughout the 1930s and 1940s with his flying wing aircraft, but the story of the YB-49 really begins with the YB-35, its piston-engined predecessor. And the story of both aircraft is a frustrating tale of what might have been. In April of 1941, the US Army Air Forces, fearing the fall of England and the loss of bases in Europe, saw a need for a bomber that could attack Nazi-occupied Europe from bases on the US mainland, so they requested a new bomber that could carry 10,000 pounds of bombs on a 10,000 mile round trip. Northrop responded with their YB-35, a huge flying wing that was powered by four piston engines turning contra-rotating propellers. But the piston engines proved to be the YB-35’s Achilles heel. The engines and the propellers had never been tested together and problems with vibrations made the power plants unreliable. Jack Northrop considered them dangerous. Through a fiasco of competing interests, the Army, who supplied the engines, Hamilton Standard, the maker of the propellers, and Northrop could not agree on a resolution. So Jack Northrop himself grounded the YB-35 until a suitable powerplant could be found, or until the Army fixed the engines they had provided. But the Army now believed that the future of aviation lay with the jet engine, so they directed Northrop to replace the four propeller engines on the YB-35 with eight turbojet engines.
The re-engined flying wing was now designated the YB-49. The eight General Electric/Allision J35 turbojet engines immediately gave the YB-49 better performance, allowing the bomber to soar to 40,000 feet and exceed 520 mph in test flights. The performance validated the flying characteristics of Northrop’s design, but the trade off for this performance was was a dramatic drop in the bomber’s range. Early turbojets were notoriously thirsty, and the flying wing’s range was cut in half, thereby eliminating it from consideration as a long range strategic bomber. Even though the YB-49 lost out to the Consolidated B-36 Peacemaker, a bomber of traditional design that was likely more appealing to Army Air Forces brass, the Army ordered testing of the YB-49 to continue, and existing YB-35 airframes were slated for conversion to jet power. In all, three YB-49s were produced from converted YB-35s, and two YRB-49 reconnaissance models were built before the program was cancelled and all the aircraft scrapped. Northrop believed that the cancellation was entirely political, but there is no question that the YB-49 was over budget and behind schedule and, even though the B-36 was an essentially obsolete WWII design, it offered the Air Force a more comfortable option to the radical flying wing. The Air Force tried to make amends to Northrop by awarding the company a contract to build the F-89 Scorpion interceptor, and Northrop eventually produced just over 1,000 copies, though it’s doubtful that Jack Northrop was mollified. Despite the cancellation of the YB-49, the flying wing concept did not die in vain. Northrop’s vision was eventually vindicated with the introduction of the Northrop Grumman B-2 Spirit bomber in 1997, and Jack Northrop was allowed to see and hold a model of the Spirit a short time before his death when the project was still top secret. Northrop, unable to speak because of his illness, reportedly wrote on a sheet of paper, “Now I know why God has kept me alive all these years.” Jack Northrop died 10 months later. (US Air Force photos)
October 22, 1955 – The first flight of the Republic F-105 Thunderchief. As the nuclear bomb became the Air Force’s strategic and tactical weapon of choice in the 1950s, the idea of a fleet of high-flying strategic bombers carpeting a target with bombs was replaced by the concept of a tactical bomber or fighter-bomber flying at very high speeds and very close to the ground to penetrate enemy airspace and deliver a single nuclear weapon. Maneuverability would be sacrificed for high speed, low level handling, and long range. In response to this doctrinal shift, the design team at Republic Aviation, led by Alexander Kartveli, developed the F-105 Thunderchief, the first aircraft designed specifically for this nuclear penetration mission. The F-105 began as a private venture by Republic to find a replacement for the RF-84 Thunderflash, the ultimate development of the straight-winged F-84 Thunderjet. The US Air Force was initially interested in the project and had planned to purchase 200, but the realities of the Korean War meant that the order was reduced to just 15 aircraft. Nevertheless, Republic continued the development of the F-105, and used lessons learned from Convair’s F-102 Delta Dagger program to redesign the fuselage of the Thunderchief to take advantage of the recently discovered area rule in order to reduce transonic drag. They also developed the F-105’s characteristic forward-swept, variable-geometry air intakes to regulate airflow to the engines at high speeds. This variant entered production as the F-105B. Further development led to the F-105D, the definitive production variant and the one built in the largest numbers. The F-105D also included an all-weather attack capability provided by the AN/APN-131 navigational radar. And the Thunderchief was big. In fact, it was the largest single-seat, single-engine combat aircraft in history, weighing in at 50,000 lbs.
The F-105A, though underpowered like so many fighters of this era, still managed to break the sound barrier on its maiden flight. The redesigned F-105B, with an afterburning Pratt & Whitney J75 axial-flow turbojet, topped out at 1,420 mph, or Mach 2.15. Though the Thunderchief, or “Thud” as it was called by its pilots, was originally designed as a low level tactical bomber, it was pressed into service in the early years of the Vietnam War as the Air Force’s primary ground attack aircraft, capable of carrying a greater bomb load than the Boeing B-17 Flying Fortress or Consolidated B-24 Liberator from WWII. And though mainly used for ground attack, Thud pilots still managed to claw 27.5 North Vietnamese aircraft out of the sky. But the F-105 was vulnerable to antiaircraft defenses, and its combat losses were high. As a result, it became the first US aircraft to be withdrawn due to combat losses. The F-105B briefly served as the platform for the US Air Force Thunderbirds demonstration squadron, but after just six shows the team switched back to the North American F-100 Super Sabre after a fatal crash caused by an overstressed airframe. The F-105 was eventually phased out in favor of newer aircraft, particularly the McDonnell Douglas F-4 Phantom II, though the F-105G Wild Weasel electronic warfare variant served until the end of the Vietnam War. Ultimately, 833 Thunderchiefs were produced, and the type was finally retired in 1984. (US Air Force photo)
October 23-26, 1944 – The Battle of Leyte Gulf takes place, the largest naval battle in history and the first successful organized kamikaze attack. By October of 1944, the Allies had regained considerable territory from the Japanese, drawing ever closer to the recapture of the Philippines and the possible invasion of the Japanese homeland. Japan could not match the industrial might of the US, and the numbers of Japanese ships, aircraft, and trained pilots dwindled while those of the US and her allies only increased. As part of the planned operation to invade the Philippine island of Leyte, the Battle of Leyte Gulf was fought, the largest naval battle of the entire war and possibly the greatest naval battle in history. By this time, the Japanese fleet was numerically inferior to the American fleet, and the outcome of the battle proved to be a devastating loss for the Japanese. The battle opened when Americans submarines USS Darter (SS-227) and USS Dace (SS-247) attacked the Japanese fleet in the Palawan Passage, sinking the heavy cruisers Atago and Maya. The overall battle of Leyte Gulf eventually encompassed four smaller engagements: the Battle of the Sibuyan Sea, the Battle of Surigao Strait, the Battle of Cape Engaño and the Battle off Samar, and by the time the action came to a close on October 26, the Japanese had suffered approximately 3,000 casualties, lost 1 light carrier and 2 escort carriers, 2 cruisers, 2 destroyers, and more than 200 aircraft, losses that spelled the end of the Japanese Navy as an effective fighting force. But out the desperation in which the Japanese found themselves, the kamikaze was born. The word kamikaze is usually translated as divine wind in reference to typhoons in the years 1274 and 1281 that helped the Japanese repel Mongol invasions, and though most commonly associated with suicide air attacks, the term is not limited to aircraft. The units that carried out the missions were called tokubetsu kōgeki tai (special attack unit). Though not a common occurrence at this point in the war, pilots of both sides had deliberately crashed their aircraft into ships. But the kamikaze attacks during the Battle of Leyte Gulf were the first organized missions of the tokubetsu kōgeki tai under the direction of 1st Air Fleet commandant Vice Admiral Takijirō Ōnishi. Speaking to officers in Manila just days before the battle, Ōnishi said, “I don’t think there would be any other certain way to carry out the operation [to hold the Philippines] than to put a 250 kg bomb on a Zero and let it crash into a US carrier in order to disable her for a week.”
On October 25, five Mitsubishi A6M Zero fighters, each armed with a single bomb, attacked escort carriers of the US fleet off the Philippine coast. Four of the kamikaze aircraft were unsuccessful, but the fifth hit the escort carrier USS St. Lo (CVE-63), igniting fires which detonated the ship’s magazine. The carrier eventually sank, and killing 143 of the 889 members of her crew. Based on this initial success, the kamikaze program was expanded and, by war’s end, the Japanese had undertaken over 4,000 attacks, including missions to ram bombers attacking Japan. Ultimately, though, all the tokubetsu kōgeki tai achieved was the loss of irreplaceable pilots and aircraft. Only 14% of the kamikaze attackers got through, and only 8.5% of the ships that were hit were sunk. Those that weren’t sunk were quickly repaired. Ultimately, the damage inflicted was no greater than that achieved in 1942 by traditional tactics. (Photo of explosion of USS St. Lo via US Navy)
October 23, 1939 – The first flight of the Mitsubishi G4M. When the Japanese laid their plans for the conquest of the western Pacific, which they grandiosely called the Greater East Asia Co-Prosperity Sphere, they knew that they would have vast stretches of ocean or large swaths of Southeast Asia to cross. Their aircraft carriers would cover the ocean, but any land-based aircraft would have to have exceptional range. Work on the G4M began in 1937 as the Japanese Navy sought a replacement for the G3M, which the Allies called the “Nell,” with particular attention paid to increasing both range and speed over the earlier bomber. The G4M prototype was completed in 1939 and the bomber, Allied reporting name “Betty,” entered service in June 1941, six months prior to the Japanese attack on Pearl Harbor that pushed the United States into World War II. The Betty could fly a little more than 100 miles farther than the Nell, and had a greater maximum takeoff weight, but the increases in range and payload over the Nell were bought at a dear price to its pilots. Mitsubishi had wanted to build a four engine bomber, but they reduced it to two engines under pressure from the Japanese Navy. To save more weight, Mitsubishi chose not to fit the new medium bomber with protective armor plating for the crew or self-sealing fuel tanks. So while the Betty had exceptional range, it was extremely susceptible to gunfire from heavily armed Allied fighters, and often burst into flames with the slightest hit. Allied pilots took to calling the Betty the “one shot lighter,” while the Japanese pilots referred to it as hamaki, which means cigar, a reference to its overall shape but perhaps also an allusion to how readily it burned. The G4M formed the backbone of the Japanese bomber force and served throughout the Pacific theater. In the early years of the war, the Betty fought very effectively when it had sufficient fighter cover, but losses began to mount as the Allies gradually gained air supremacy. Final variants of the Betty did add armor protection and rudimentary sealing for the fuel tanks, but these upgrades came too late for the Betty to have a significant impact on the outcome of the war. By the final stages of WWII, with dwindling numbers of Japanese fighters to protect them, Bettys were mauled by US Navy and US Army Air Corps fighters and many of the bombers were shot down before they could launch their attacks.
In addition to its land bombing duties, the Betty was also used to bomb shipping and as a torpedo bomber, and, late in the war, it served as the mother ship for the Yokosuka MXY7 Ohka suicide aircraft, a rocket-powered, piloted bomb with 2,646 pounds of explosives in the nose used for kamikaze attacks. The Betty also took center stage in a pivotal event in the Pacific War, when Japanese General Isoroku Yamamoto, the architect of the Pearl Harbor attack and commander in chief of the Japanese combined fleet, was shot down and killed in 1943 while flying as a passenger in a G4M during an inspection tour of Japanese bases. More than 2,400 G4Ms were produced, but no flyable examples remain today, and only one complete aircraft remains. (Photo authors unknown)
October 24, 1953 – The first flight of the Convair F-102 Delta Dagger. Following WWII, US Air Force planners became particularly enamored with the guided missile, thinking that all future aerial combat would take place between fighters that lobbed missiles at each other rather than duke it out in aerial dogfights. But firing missiles accurately required an effective fire control system (FCS), so the Air Force decided first to develop an integrated radar, computer, director and missile system, and then find a plane to put it in. In January 1950, the Air Force requested proposals for a new FCS, and the competition for its development was eventually won by Hughes Aircraft with their AIM-4 Falcon missile, the first operational guided air-to-air missile fielded by the Air Force. With the missile system in hand, the Air Force sought proposals in June of that year for what they dubbed the “1954 Ultimate Interceptor” to deal with the threat of waves of Russian strategic bombers flying towards the US. Convair, Republic and Lockheed all submitted proposals, but only Convair was selected to proceed with development. Convair developed the first Delta Dagger from their XF-92, a delta-winged interceptor it had developed in the late 1940s, enlarging the experimental aircraft and mounting a Pratt & Whitney J57 afterburning turbojet. Once the first prototypes were finished, however, Convair discovered that the YF-102 was unable to break the sound barrier, and the problem wasn’t just the underpowered engine. It was the shape of the fuselage.
Using the new area rule concept developed by NACA engineer Richard Whitcomb, Convair redesigned the fuselage so that it narrowed at the waist over the delta wing. Reducing the aircraft’s cross section dramatically reduced its drag, and other improvements to the wings allowed the redesigned interceptor to pass Mach 1 with ease. The redesigned aircraft was called the YF-102A, and it was this model that first entered production after its maiden flight in December 1954. The F-102A entered service in April 1956, and a total of 889 were built before production ceased in September 1958. The Delta Dagger saw service in Vietnam primarily as a bomber escort, though some ground attack missions were carried out without much success since the aircraft was not designed for that role, nor were the pilots properly trained. Fourteen F-102s were lost in combat, one in air-to-air combat. The F-102 was exported to Greece and Turkey, where they served into the late 1970s. The F-102 was retired from active service with the US Air Force in 1976, and many Delta Daggers were converted to QF-102A target drones, with the final one being shot down in 1986. (US Air Force photo; NASA photo)
October 21, 1966 – The first flight of the Yakovlev Yak-40, the world’s first commuter trijet and one specifically designed to operate from poorly equipped airports with short or unimproved runways. The Yak-40 was developed to take over shorter routes from obsolete piston-powered airliners and could carry up to 32 passengers with a range of just over 1,000 miles. Over 1,000 were produced from 1967-1981, and they provided local service throughout Russia and served over 30 international customers. The Yak-4o remains in service today. (Photo by Eduard Heisterkamp via Wikimedia Commons)
October 21, 1961 – The first flight of the Breguet Atlantique, a turboprop-powered, long-range maritime patrol aircraft that was designed to perform reconnaissance and anti-submarine warfare (ASW) missions and developed to replace the Lockheed P2V Neptune then in service with NATO forces. Aircraft were delivered in two batches, with 87 Atlantique 1 aircraft built from 1965 to 1968. The Atlantique 2 was produced from 1972 to 1974 with more powerful engines, new avionics, and the ability to fire the Exocet anti-shipping missile. A total of 115 of both variants were produced. (Photo by Arpingstone via Wikimedia Commons)
October 21, 1950 – The first flight of the Martin 4-0-4. The Glenn L. Martin Company made its first serious foray into the civilian airliner business when it developed the Martin 2-0-2 to compete with the Douglas DC-3. The 2-0-2 was unpressurized, and after production was stopped due to structural faults, instead of fixing the 2-0-2 they developed it into the pressurized 4-0-4. Martin also stretched it to accommodate up to 40 passengers. The 4-0-4 entered service with Eastern Air Lines and TWA in 1951, as well as the US Coast Guard who two to be flown as executive aircraft designated the VC-3. When superseded by newer turboprop airliners, the 4-0-4 continued to serve smaller regional airlines and charters into the 1980s. A total of 103 were produced from 1951-1953. (Photo by John Proctor via Wikimedia Commons)
October 21, 1942 – An aircraft carrying American WWI ace Eddie Rickenbacker ditches in the Pacific Ocean. Rickenbacker was publicly sent on an inspection tour of American bases in the Pacific Theater, but the true nature of his mission was to deliver a message of rebuke to General Douglas MacArthur from President Franklin Roosevelt for negative comments the general had made about the administration. The Boeing B-17D Flying Fortress departed Hawaii, but then strayed hundreds of miles off course and was forced to ditch in the Pacific Ocean far from normal travel routes. Rickenbacker and the crew drifted in life rafts for 24 days before a US Navy Vought OS2U Kingfisher crew finally spotted and rescued the seven survivors. After his recovery, Rickenbacker completed his mission to deliver the letter to MacArthur. (US Army, US Navy photos)
October 23, 2003 – The Concorde makes its final passenger flight. Air France had made its final passenger flights on May 30, 2003, and British Airways finally ended Concorde service with a flight from from John F. Kennedy International Airport in New York to Heathrow Airport in London, while two other Concordes made round trips over the Bay of Biscay and to Edinburgh, Scotland. All three aircraft then circled London before landing. The flights closed the book on the Concorde, the world’s first operational supersonic passenger airliner, which entered service with British Airways in 1976. Following a crash in 2000, Concorde flights were suspended for a year, but, after returning to service in 2001, the Concorde remained unprofitable and BA and Air France suspended operations. (Photo by Eduard Marmet via Wikimedia Commons)
October 23, 1967 – The first flight of the Canadair CL-215, also known as the Scooper, the first in a series of amphibious firefighting aircraft developed by Canadair and later Bombardier Aerospace. Powered by two Pratt & Whitney R-2800 Double Wasp radial engines, the CL-215 can scoop 1,440 US gallons of water in 12 seconds from lakes or rivers and drop it over wildfires, and special design considerations such as its high, straight wing allow for operations at low speeds or in the gusty conditions often found over forest fires. A total of 125 were produced, and the CL-215 was subsequently developed into the CL-215T and CL-415 which are powered by two turboprop engines. (Photo by Alan Radecki via Wikimedia Commons)
October 23, 1952 – The first flight of the Hughes XH-17, a super heavy lift helicopter and the first project developed by the helicopter division of Hughes Aircraft. Built from parts scavenged from several different aircraft, the XH-17 was capable of lifting over 10,000 pounds with a maximum takeoff weight of 43,500 pounds. The XH-17 was powered by two turbojet engines that ducted bleed air through the hollow rotor blades to tip-mounted jets, and still holds the record for the world’s largest rotor system. Only one was built before the program was cancelled and the aircraft scrapped. (US Government photo)
October 23, 1951 – The last daylight bombing mission of the Boeing B-29 Superfortress. With the B-29, the development of large four-engine bombers reached its zenith by the end of WWII, but the advanced design saw the Superfortress fly beyond the war and into the Korean War. At first, the B-29s flew daylight bombing missions as they had in WWII, but the arrival of jet fighters made the slower bombers vulnerable to being shot down. The final daylight mission was an attack on an airfield in North Korea, but three of the 10 bombers were shot down, four were forced to make emergency landings in South Korea, and three were badly damaged but still able to return to Okinawa. The B-29s were switched to nighttime bombing missions before being withdrawn in 1953. (US Air Force photo)
October 24, 2004 – A plane crash claims the life of members of the Hendrick Motorsports team and family. While en route from North Carolina to a race at Martinsville Speedway in Virginia, a Beechcraft King Air 200 (N501RH) carrying members of the Hendrick Motorsport team and other family members crashed in heavy fog after an aborted landing. Among the 10 victims was the president of Hendrick Motorsports John Hendrick, driver Ricky Hendrick, four other members of the Hendrick family and Randy Dorton, chief engine builder. The pilots were also killed. Though NASCAR officials learned of the crash before the race, they did not tell the drivers until after the race had finished. The race was won by Jimmie Johnson, who drove for the Hendrick team. For the remainder of the 2004 season, all Hendrick cars ran with a memorial to the victims, “Always In Our Hearts,” painted on the hood. (Photo via Motorsport.com)
October 24, 2000 – The first flight of the Lockheed Martin X-35, the experimental prototype developed as part of the competition to produce the Joint Strike Fighter that would serve the US Air Force, US Navy and US Marine Corps. The competition for the lucrative contract pitted the X-35 against the Boeing X-32, with the X-35 declared the winner on October 26, 2001. It entered production in 2006 as the F-35 Lighting II, a single-seat, all-weather, multi-role, fifth-generation fighter with stealth capability. The F-35 is being produced in three variants, one each for the Air Force (F-35A), Marine Corps (F-35B) and Navy (F-35C), with the F-35B capable of vertical takeoff and landing. (US Air Force photo)
October 24, 1947 – The first flight of the Grumman HU-16 Albatross, a twin-engine amphibious flying boat designed as an improvement over the earlier Grumman G-73 Mallard. The Albatross entered service in 1949 primarily in the search and rescue (SAR) and combat search and rescue (CSAR) role with the US Air Force where it was initially known as the SA-16, and saw extensive service during the Korean War rescuing downed pilots. The Albatross was also operated by the US Navy and US Coast Guard, where it functioned as a coastal patrol and SAR aircraft. The Albatross was widely exported, and many surplus aircraft found their way to private operators. A total of 466 were produced from 1949-1961. (Photo by Alan Radecki via Wikimedia Commons)
October 24, 1919 – The birth of Frank Piasecki, an engineer and pioneer in the development of tandem rotor helicopters. Piasecki also created the concept of the compound helicopter using vectored thrust from a ducted propeller (VTDP). Piasecki founded the Piasecki Helicopter Corporation in 1940 and produced the PV-2, the second successful helicopter in the US after the Sikorsky VS-300. He followed that with a series of tandem rotor helicopters, including the H-21 Shawnee, which served in Vietnam as a troop transport until 1964. In 1956, Piasecki was ousted from the company he founded, so he started a new company called Piasecki Aircraft (his former company became Vertol, and was eventually sold to Boeing). Currently, Piasecki Aircraft is working on the X-49 Speedhawk, a Sikorsky YSH-60F Seahawk, that was modified to use a ducted tail fan to achieve higher speeds than those possible with a traditional helicopter. Piasecki died in 2008. (Photo author unknown)
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