Daily Archives: April 11, 2024

11 April 1975

A formation of NASA's five Lockheed F-104 Starfighters, 11 April 1975. (NASA/Bob Rhine)
A formation of NASA’s five Lockheed F-104 Starfighters, 11 April 1975. (NASA/Bob Rhine)

11 April 1975: “The only time the five ship fleet of NASA Dryden’s F-104 Starfighters was ever airborne at the same time. Pilots were: F-104N #811-Bill Dana; F-104N #812-Tom McMurtry; F-104A #818-Einar Enevoldson; F-104A #820-Gary Krier; and F-104B #819-Fitz Fulton and Ray Young. Photo taken from T-38 #821 flown by Don Mallick.”

11 April 1970, 19:13:00.65 UTC, Range Zero + 000:00:00.65

Apollo 13 (AS-508) lifts off from Launch Complex 39A at the Kennedy Space Center, Cape Canaveral, Florida, 19:13:00 UTC, 11 April 1970. (NASA)
Apollo 13 (AS-508) lifts off from Launch Complex 39A at the Kennedy Space Center, Cape Canaveral, Florida, 19:13:00 UTC, 11 April 1970. (NASA)

11 April 1970: At 2:13:00 p.m., Eastern Standard Time, Apollo 13 was launched from Launch Complex 39A at  the Kennedy Space Center, Cape Canaveral, Florida. This mission was planned to be the third manned lunar landing. The destination was the Fra Mauro Highlands. In command was Captain James A. Lovell, Jr., United States Navy. The Command Module Pilot was John L. “Jack” Swigert, Jr. (who was originally scheduled as the backup CSM pilot, but had replaced Lieutenant Commander T. Kenneth Mattingly II, USN, just three days before launch). and the Lunar Module Pilot was Fred W. Haise, Jr., A NASA astronaut (formerly a U.S. Marine Corps and U.S. Air Force fighter pilot, test pilot and instructor).

Apollo 13 flight crew, left to right: James A. Lovell, Jr., John L. Swigert, Jr., Fred W. Haise, Jr. (NASA)

The crew change had been made because it was believed that Ken Mattingly had been exposed to measles and NASA administrators did not want to risk that he might become ill during the flight.

The F-1 engines of the S-IC first stage shut down at 2 minutes, 43.6 seconds. After being jettisoned, the first stage continued on a ballistic trajectory and fell into the Atlantic Ocean at 000:09:52.64, 355.3 nautical miles (408.9 statute miles/658.0 kilometers) from the launch site.

At T + 000:05:30.64, while accelerating toward Earth orbit, the center J-2 engine on the Saturn S-II second stage shut down 2 minutes, 12.36 seconds early, which required the other four engines to increase their burn by 34.53 seconds, and the S-IVB third stage engine had to burn 9 seconds seconds longer than planned to achieve the necessary velocity for orbital insertion. The second stage traveled 2,452.6 nautical miles (2,822.4 statute miles/4,542.2 kilometers) before hitting the Atlantic’s surface at T + 20 minutes, 58.1 seconds.

Following the Trans Lunar Injection maneuver, Apollo 13’s S-IVB third stage was intentionally crashed into the lunar surface. The impact took place at 00:09:41 UTC, 15 April. The stage was traveling at 5,600 miles per hour (9,012 kilometers per hour). The energy at impact was equivalent to the explosion 7.7 tons of TNT.

The Apollo 13 mission did not go as planned. An explosion inside the service module was a very near disaster, and the lunar landing had to be aborted. Returning the three astronauts safely to Earth became the primary task.

Damage to Apollo 13’s Service Module, photographed just after separation. (NASA)

The Saturn V rocket was a three-stage, liquid-fueled heavy launch vehicle. Fully assembled with the Apollo Command and Service Module, it stood 363 feet (110.642 meters) tall. The first and second stages were 33 feet (10.058 meters) in diameter. Fully loaded and fueled the rocket weighed 6,200,000 pounds (2,948,350 kilograms). It could lift a payload of 260,000 pounds (117,934 kilograms) to Low Earth Orbit.

Apollo 13/Saturn V (AS-508) during rollout, 16 December 1969. (NASA 69-HC-1269)

The first stage was designated S-IC. It was designed to lift the entire rocket to an altitude of 220,000 feet (67,056 meters) and accelerate to a speed of more than 5,100 miles per hour (8,280 kilometers per hour). The S-IC stage was built by Boeing at the Michoud Assembly Facility, New Orleans, Louisiana. It was 138 feet (42.062 meters) tall and had an empty weight of 290,000 pounds (131,542 kilograms). Fully fueled with 203,400 gallons (770,000 liters) of RP-1 and 318,065 gallons (1,204,000 liters) of liquid oxygen, the stage weighed 5,100,000 pounds (2,131,322 kilograms). It was propelled by five Rocketdyne F-1 engines, producing 1,522,000 pounds of thrust, each, for a total of 7,610,000 pounds of thrust at Sea Level. These engines were ignited seven seconds prior to lift off and the outer four burned for 168 seconds. The center engine was shut down after 142 seconds to reduce the rate of acceleration. The F-1 engines were built by the Rocketdyne Division of North American Aviation at Canoga Park, California.

Saturn V first stage Rocketdyne F-1 engines running, producing 7.5 million pounds of thrust. Ice falls from the rocket. The hold-down arms have not yet been released. (NASA)

The S-II second stage was built by North American Aviation at Seal Beach, California. It was 81 feet, 7 inches (24.87 meters) tall and had the same diameter as the first stage. The second stage weighed 80,000 pounds (36,000 kilograms) empty and 1,060,000 pounds loaded. The propellant for the S-II was liquid hydrogen and liquid oxygen. The stage was powered by five Rocketdyne J-2 engines, also built at Canoga Park. Each engine produced 232,250 pounds of thrust, and combined, 1,161,250 pounds of thrust.

The Saturn V third stage was designated S-IVB. It was built by McDonnell Douglas Astronautics Company at Huntington Beach, California. The S-IVB was 58 feet, 7 inches (17.86 meters) tall with a diameter of 21 feet, 8 inches (6.604 meters). It had a dry weight of 23,000 pounds (10,000 kilograms) and fully fueled weighed 262,000 pounds. The third stage had one J-2 engine and also used liquid hydrogen and liquid oxygen for propellant. The S-IVB would place the Command and Service Module into Low Earth Orbit, then, when all was ready, the J-2 would be restarted for the Trans Lunar Injection.

Eighteen Saturn V rockets were built. They were the most powerful machines ever built by man.

© 2019, Bryan R. Swopes

Medal of Honor, Airman 1st Class William Hart Pitsenbarger, United States Air Force

Airman 1st Class William Hart Pitsenbarger, United States Air Force

The President of the United States of America, authorized by Act of Congress, March 3, 1863 has awarded in the name of the Congress the Medal of Honor posthumously to:

for conspicuous gallantry and intrepidity in action at the risk of his life above and beyond the call of duty Near Cam My, 11 April 1966:

Rank and organization: Airman First Class, U.S. Air Force, Detachment 6, 38th Aerospace Rescue and Recovery Squadron, Bien Hoa Air Base, Republic of Vietnam.

Place and date: Near Cam My, 11 April 1966

Entered service at: Piqua, Ohio

Born: 8 July 1944, Piqua, Ohio

Citation: Airman First Class Pitsenbarger distinguished himself by extreme valor on 11 April 1966 near Cam My, Republic of Vietnam, while assigned as a Pararescue Crew Member, Detachment 6, 38th Aerospace Rescue and Recovery Squadron. On that date, Airman Pitsenbarger was aboard a rescue helicopter responding to a call for evacuation of casualties incurred in an on-going firefight between elements of the United States Army’s 1st Infantry Division and a sizable enemy force approximately 35 miles east of Saigon. With complete disregard for personal safety, Airman Pitsenbarger volunteered to ride a hoist more than one hundred feet through the jungle, to the ground. On the ground, he organized and coordinated rescue efforts, cared for the wounded, prepared casualties for evacuation, and insured that the recovery operation continued in a smooth and orderly fashion. Through his personal efforts, the evacuation of the wounded was greatly expedited. As each of the nine casualties evacuated that day were recovered, Pitsenbarger refused evacuation in order to get one more wounded soldier to safety. After several pick-ups, one of the two rescue helicopters involved in the evacuation was struck by heavy enemy ground fire and was forced to leave the scene for an emergency landing. Airman Pitsenbarger stayed behind, on the ground, to perform medical duties. Shortly thereafter, the area came under sniper and mortar fire. During a subsequent attempt to evacuate the site, American forces came under heavy assault by a large Viet Cong force. When the enemy launched the assault, the evacuation was called off and Airman Pitsenbarger took up arms with the besieged infantrymen. He courageously resisted the enemy, braving intense gunfire to gather and distribute vital ammunition to American defenders. As the battle raged on, he repeatedly exposed himself to enemy fire to care for the wounded, pull them out of the line of fire, and return fire whenever he could, during which time, he was wounded three times. Despite his wounds, he valiantly fought on, simultaneously treating as many wounded as possible. In the vicious fighting which followed, the American forces suffered 80 percent casualties as their perimeter was breached, and airman Pitsenbarger was finally fatally wounded. Airman Pitsenbarger exposed himself to almost certain death by staying on the ground, and perished while saving the lives of wounded infantrymen. His bravery and determination exemplify the highest professional standards and traditions of military service and reflect great credit upon himself, his unit, and the United States Air Force.

Airman 1st Class William Hart Pitsenbarger, United States Air Force, with his Colt M-16 rifle and Kaman HH-43 Huskie rescue helicopter. (U.S. Air force)
Medal of Honor
Medal of Honor

© 2017, Bryan R. Swopes

11 April 1952

Piasecki YH-21-PH Work-Horse 50-1231, first flight at Morton Grove, PA. (San Diego Air and Space Museum Archives)
Piasecki YH-21-PH Work-Horse 50-1231, first flight at Morton Grove, PA. (San Diego Air and Space Museum Archives)

11 April 1952: At the Piasecki Helicopter Corporation factory at Morton Grove, Pennsylvania, the first YH-21 tandem-rotor helicopter, serial number 50-1231, made it’s first flight. The test pilots were Leonard Joseph (“Len”) LaVassar and Martin P. (“Marty”) Johnson, both former U.S. Navy aviators.

The Piasecki Helicopter Corporation built 18 pre-production YH-21-PH helicopters, followed by three production variants, the H-21A, H-21B and H-21C.

The U.S. Air Force immediately ordered 32 H-21A helicopters for Search and Rescue operations. The Workhorse was well suited to cold weather operations and it was widely used in Alaska, Canada, and the Antarctic. Another 163 H-21B models were ordered as a troop transports. The U.S. Army ordered a similar H-21C variant.

Piasecki YH-21, left profile.
Piasecki YH-21 Work Horse 50-1231, with rotors turning.

The YH-21 was a single-engine, tandem-rotor transport helicopter. It was normally operated by two pilots, with a flight mechanic (crew chief), and could carry up to 20 soldiers under ideal conditions.

With rotors turning, the YH-21’s overall length was 86 feet, 5 inches (26.340 meters). The fuselage was 52 feet, 6 inches (16.002 meters) long, and the helicopter had an overall height of 16 feet, 0 inches (4.877 meters). The rotors were 44 feet, 0 inches (13.411 meters) in diameter. The YH-21’s empty weight was approximately 8,117 pounds (3,682 kilograms) and maximum gross weight was 14,500 pounds (6,577 kilograms).

Piasecki H-21B Workhorse 51-3433 at Elmendorf Air Force Base, Alaska, circa 1960. (U.S. Air Force)

The forward rotor turned counter-clockwise, as seen from above. (The advancing blade is on the helicopter’s right side.) The rear rotor turns the opposite direction. Normal operating speed for the main rotors was 233 to 258 r.p.m. (233–270 r.p.m. in autorotation.) The counter-rotating rotors cancelled out engine torque, eliminating any need for a tail rotor. The angle in the fuselage was intended to provide adequate vertical clearance between the intermeshing fore and aft rotor assemblies. (Later tandem rotor helicopters use raised pylons.)

Piasecki HH-21B 51-15855 supported X-15 flight operations at Edwards Air Force Base. (NASA)

The H-21 was powered by a single air-cooled, supercharged, 1,823.129-cubic-inch-displacement (29.875 liter) Wright Aeronautical Division Cyclone 9 863C9WD1 (R-1820-103) nine-cylinder radial, mounted inside the fuselage at midship, and drove the front and rear rotors in opposite directions through drive shafts and gear boxes. The Wright R-1820-103 engine was rated at 1,275 horsepower at 2,500 r.p.m., and 1,425 horsepower at 2,700 r.p.m., for takeoff. This direct-drive engine had a compression ratio of 6.80:1 and required 100/130 aviation gasoline. The engine was 4 feet, 0.50 inches (1.232 meters) long, 4 feet, 6.95 inches (1.396 meters) in diameter, and weighed 1,350 pounds (612 kilograms). Wright built 971 R-1820-103s from November 1950 through 1957.

The YH-21 could reach a maximum speed in level flight of 131 knots (151 miles per hour/243 kilometers per hour). Its Never Exceed limit (VNE) was 151 knots (174 miles per hour /280 kilometers per hour) (diving). The maximum Sea Level range was 397 nautical miles (457 statute miles/735 kilometers) at 125 knots (144 miles per hour/232 kilometers per hour). Its service ceiling was 19,200 feet (5,852 meters).

In 1955, Piasecki became Vertol and eventually Boeing Vertol. The company would continue to produce tandem rotor helicopters such as the H-46 Sea Knight and the CH-47 Chinook, which is still in production.

Piasecki CH-21B Workhorse, 51-15857, at the National Museum of the United States Air Force. (U.S. Air Force)
Piasecki CH-21B Workhorse, 51-15857, at the National Museum of the United States Air Force. (U.S. Air Force)

© 2019, Bryan R. Swopes

11 April 1945

Lt. Merritt Duane Francies (left) and Lt. William S. Martin with a Piper L-4J Grasshopper, 44-80699 (54 ☆ G) (Passion Aviation)

11 April 1945: 1st Lieutenant Merritt Duane Francies, Field Artillery, USA, and forward observer Lieutenant William S. Martin, 71st Armored Field Artillery Battalion, 5th Armored Division, were flying a Piper L-4H Grasshopper on a reconnaissance mission near Dannenberg, Germany. This was Francies’ 142nd combat mission.

The Grasshopper (Piper Model J3C-65D) was named Miss Me!? Its U.S. Army serial number was 43-29905, and it was marked 54 ☆ J.

The two airmen saw an enemy Fieseler Fi 156 Storch flying beneath them. The Storch was similar to the Grasshopper. Both were single engine, high-wing monoplanes with fixed landing gear. The Storch was larger and faster, but both airplanes had similar missions during the War.

A Fieseler Fi 156 Storch, SJ+LL, Gran Sasso d’Italia, 12 September 1943. (Bundsarchiv, Bild 101I-567-1503C-04)

Francies put his L-4H into a dive and overtook the Luftwaffe airplane. Both American officers carried M1911 .45-caliber semi-automatic pistols, with which they fired on the Fieseler. Both officers emptied the 7-round magazines, then reloaded. The enemy airplane began to circle.

U.S. Pistol, Automatic, Caliber .45, M1911.

Lieutenant Francies approached again, coming to within an estimated 30 feet (9 meters) of the German airplane. Both opened fire again, striking the Storch in the windshield and in a fuel tank. It went into a spin, then crashed. Francies landed his airplane nearby.

The two German crewmen got out of the wrecked Fi 156 and tried to run, but the observer had been wounded in the foot. Lieutenant Martin fired a warning shot and the German pilot stopped, then surrendered.

The captured airmen were turned over to an American tank crew. Francies later said, “I never found out their names. They could have been important, for all I know. We turned them over to our tankers about 15 minutes later after the injured man thanked me many times for bandaging his foot. I think they thought we would shoot them.”

Francies and Martin with their kill
Duane Francies, Freshman, (The Cascade 1940)

Merritt Duane Francies was born 21 July 1921. He was the son of Merritt Charles Francies, a fruit farmer, and Kathleen I. Horan Francies. He studied at Seattle Pacific College for one year before he enlisted as private, Air Corps, United States Army, 10 December 1941, at Spokane, Washington. Private Francies was 5 feet, 10 inches (1.78 meters) tall and weighed 170 pounds (77 kilograms).

2nd Lieutenant Francies had trained as a pilot and was assigned to an L-4 light observation airplane to conduct reconnaissance for the 5th Armored Division. On 19 September 1944 he rescued a wounded forward observer, for which he was awarded the Bronze Star. He was awarded an Air Medal on 27 September 1944. Francies received a battlefield promotion to 1st lieutenant, 15 January 1945.

Following the air-to-air battle with the Storch, Lieutenant Francies was recommended for the Distinguished Flying Cross, 24 April 1945. Major General Walter Jensen, 14th Army Corps, present the medal to him 22 years later, 13 March 1967.

Duane Francies married Miss Jo Ann Hulson in Lake County, Indiana, 29 March 1947. He died at Chelan, Washington, 5 May 2004.

A Piper J-3C-65 Cub, NX38505, in U.S. Army Markings, Louisiana, 1941. The second airplane is a Stinson O-49. (Hans Groenhoff Collection NASM SI-2004-51347)

The Piper L-4H Grasshopper is a single-engine, two-place strut-braced high-wing monoplane based on the civilian Piper J-3C Cub. In military service, it was used as a short-range reconnaissance and liaison aircraft. The cockpit had a tandem configuration. The airplane was constructed of a welded steel tube fuselage, and the wings had wooden spars and riveted aluminum ribs. It was covered with doped fabric.

The L-4H was 22 feet, 4½ inches (6.820 meters) long, with a wingspan of 35 feet, 2½ inches (10.732 meters). Its height, when parked in 3-point attitude, was 8 feet, 6 inches (2.591 meters) to the top of the propeller arc. The wing has a chord of 5 feet, 3 inches (1.600 meters) and a total area of square feet ( square meters). It has an angle of incidence of 1° 37′ and 0° 41′ negative twist. The variable incidence horizontal stabilizer has a span of 9 feet, 6 inches (2.896 meters). The Piper L-4H Grasshopper had an approximate empty weight of 740 pounds (336 kilograms), depending on installed equipment, and a maximum gross weight of 1,220 pounds (553 kilograms).

Piper L-4 Grasshopper (T. O. NO. 01-140DA-3, Structural Repair Instructions, at Page 2)

The Grasshopper was powered by an air-cooled, normally-aspirated, 171.002-cubic-inch-displacement (2.802 liter) Continental O-170-3 (Continental A65-8), horizontally-opposed four-cylinder overhead-valve engine with a compression ratio of 6.3:1. It was rated at 65 horsepower at 2,300 r.p.m. at Sea Level for takeoff, and required a minimum of 73-octane gasoline. The direct-drive engine turned a two-blade fixed-pith propeller with a diameter of 6 feet, 0 inches (1.829 meters).

The L-4H had a maximum speed of 90 miles per hour (145 kilometers per hour), and an absolute ceiling of 14,000 feet (4,267 meters). With a fuel capacity of 12 U.S. gallons (45.4 liters), its maximum range was 206 miles (332 kilometers).

Piper J-3C Cub. (Hans Groenhoff Collection, NASM-HGC-1121)

© 2019, Bryan R. Swopes