Pan Am Flight 526A, a

Douglas DC-4 The Douglas DC-4 is an American four-engined (piston), propeller-driven airliner developed by the Douglas Aircraft Company. Military versions of the plane, the C-54 and R5D, served during World War II, in the Berlin Airlift and into the 1960s ...

, took off from

San Juan-Isla Grande Airport Fernando Luis Ribas Dominicci Airport , also commonly known as Isla Grande Airport, is an airport in Isla Grande (Santurce), Isla Grande, a district in the municipality of San Juan, Puerto Rico. It is owned by the Puerto Rico Ports Authority and ...

Puerto Rico Puerto Rico (; abbreviated PR; tnq, Boriken, ''Borinquen''), officially the Commonwealth of Puerto Rico ( es, link=yes, Estado Libre Asociado de Puerto Rico, lit=Free Associated State of Puerto Rico), is a Caribbean island and Unincorporated ...

, at 12:11 PM AST on April 11, 1952 on a flight to

Idlewild International Airport John F. Kennedy International Airport (colloquially referred to as JFK Airport, Kennedy Airport, New York-JFK, or simply JFK) is the main international airport serving New York City. The airport is the busiest of the seven airports in the New ...

New York City New York, often called New York City or NYC, is the List of United States cities by population, most populous city in the United States. With a 2020 population of 8,804,190 distributed over , New York City is also the L ...

with 64 passengers and five crew members on board.Accident Description Pan Am Flight 526A
, ''

Aviation Safety Net The Flight Safety Foundation (FSF) is an independent, nonprofit, international organization concerning research, education, advocacy, and communications in the field of aviation safety. FSF brings together aviation professionals from all sectors ...

'' Due to inadequate maintenance, engine no. 3 failed after

takeoff Takeoff is the phase of flight in which an aerospace vehicle leaves the ground and becomes airborne. For aircraft traveling vertically, this is known as liftoff. For aircraft that take off horizontally, this usually involves starting with a t ...

, followed shortly by engine no. 4.Accident Details Pan Am Flight 526A

''PlaneCrashInfo.com''
Nine minutes after takeoff, the aircraft

ditched In aviation, a water landing is, in the broadest sense, an Landing, aircraft landing on a body of water. Seaplanes, such as floatplanes and flying boats, land on water as a normal operation. Ditching is a controlled emergency landing on the ...

in rough seasAccident Description Pan Am Flight 526A

''PanAmAir.org''
11.3 miles NW of San Juan Airport, broke apart and sank after three minutes. Panicking passengers refused to leave the sinking wreck.A Tragic Good Friday 1952
, by ''J. R. Lee, AOC, USCG, Retired'' and ''Ted A. Morris, Lt. Col., USAF, Retired'' 52 passengers were killed, and 17 passengers and crew members were rescued by the

USCG The United States Coast Guard (USCG) is the maritime security, search and rescue, and law enforcement service branch of the United States Armed Forces and one of the country's eight uniformed services. The service is a maritime, military, mu ...

."1947 - Coast Guard Air Detachment San Juan Puerto Rico Established"

''United States Coast Guard Aviation History''
After this accident it was recommended to implement

pre-flight safety demonstration A pre-flight safety briefing (also known as a pre-flight demonstration, in-flight safety briefing, in-flight safety demonstration, safety instructions, or simply the safety video) is a detailed explanation given before take-off to airline passeng ...

s for over-water flights.

Aircraft

The

piston aircraft with four

propellers A propeller (colloquially often called a screw if on a ship or an airscrew if on an aircraft) is a device with a rotating hub and radiating blades that are set at a pitch to form a helical spiral which, when rotated, exerts linear thrust upon ...

had made its first flight in 1945 and had 20,835 airframe hours.

Accident

On a sunny day with a gentle breeze, Pan Am Flight 526A, a Douglas DC-4 named ''Clipper Endeavor'',Pan Am Clipper Names

''PanAmAir.org''
took off from San Juan Airport at 12:11 PM on

Good Friday Good Friday is a Christian holiday commemorating the crucifixion of Jesus and his death at Calvary. It is observed during Holy Week as part of the Paschal Triduum. It is also known as Holy Friday, Great Friday, Great and Holy Friday (also Hol ...

of 1952 on a flight to Idlewild Airport, NY (now known as

JFK John Fitzgerald Kennedy (May 29, 1917 – November 22, 1963), often referred to by his initials JFK and the nickname Jack, was an American politician who served as the 35th president of the United States from 1961 until his assassination i ...

). Sixty-four passengers and five crew members were on board, including Captain John C. Burn, a well-qualified, seasoned pilot, in command. Just after takeoff, engine

no. 3 ''No. 3'' () is a 1997 Koreans, South Korean Kkangpae, gangster comedy film starring Han Suk-kyu as the titular no. 3 man of a gang who's aspiring to rise up the ranks and become the leader of his own gang. It was writer-director Song Nung-han's ...

failed at 350 feet and the propeller was feathered (its blades were turned parallel to the direction of flight to avoid drag) by the flight crew. The pilots decided to return to San Juan Airport, reversed their

heading Heading can refer to: * Heading (metalworking), a process which incorporates the extruding and upsetting processes * Headline, text at the top of a newspaper article * Heading (navigation), the direction a person or vehicle is facing, usually si ...

, and managed to continue climbing to 550 feet when engine no. 4 failed as well. With both engines on the right wing inoperable, the ''Clipper Endeavor'' was not able to maintain altitude any longer."Engine Failure During Flight (Chapter 12 pages 21-31)"

Airplane Flying Handbook
''

Federal Aviation Administration The Federal Aviation Administration (FAA) is the largest transportation agency of the U.S. government and regulates all aspects of civil aviation in the country as well as over surrounding international waters. Its powers include air traffic m ...

'' Captain Burn declared an in-flight emergency and informed the control tower that he planned to attempt a

water landing In aviation, a water landing is, in the broadest sense, an aircraft landing on a body of water. Seaplanes, such as floatplanes and flying boats, land on water as a normal operation. Ditching is a controlled emergency landing on the water ...

approximately seven miles NNW off Isla Grande. Fifteen-

knot A knot is an intentional complication in cordage which may be practical or decorative, or both. Practical knots are classified by function, including hitches, bends, loop knots, and splices: a ''hitch'' fastens a rope to another object; a ' ...

winds whipped up the sea when the ''Clipper Endeavor'' ditched into the Atlantic Ocean north of San Juan at 12:20 PM. The rear

fuselage The fuselage (; from the French ''fuselé'' "spindle-shaped") is an aircraft's main body section. It holds crew, passengers, or cargo. In single-engine aircraft, it will usually contain an engine as well, although in some amphibious aircraft t ...

broke off behind the bulkhead of the main cabin and the wreckage sank in fewer than three minutes. Survivors later reported that many passengers had survived the initial ditching but had panicked because they feared the rough seas and the possibility of sharks and had refused to leave the sinking aircraft to board life rafts.

Rescue

After having received Captain Burn's emergency transmission, the tower notified the USCG rescue center and a

PBY-5A Catalina The Consolidated PBY Catalina is a flying boat and amphibious aircraft that was produced in the 1930s and 1940s. In Canadian service it was known as the Canso. It was one of the most widely used seaplanes of World War II. Catalinas served w ...

flying boat A flying boat is a type of fixed-winged seaplane with a hull, allowing it to land on water. It differs from a floatplane in that a flying boat's fuselage is purpose-designed for floatation and contains a hull, while floatplanes rely on fusela ...

under the command of Lieutenant Ted Rapalus was airborne within 6 minutes. The USCG's second PBY was undergoing routine maintenance and had the

auxiliary power unit An auxiliary power unit (APU) is a device on a vehicle that provides energy for functions other than propulsion. They are commonly found on large aircraft and naval ships as well as some large land vehicles. Aircraft APUs generally produce 115&n ...

including

bilge pump A bilge pump is a water pump used to remove bilge water. Since fuel can be present in the bilge, electric bilge pumps are designed to not cause sparks. Electric bilge pumps are often fitted with float switches which turn on the pump when the bilge ...

removed. Due to the gravity of the emergency the PBY was removed from maintenance status and under the command of Lieutenant Commander Ken Bilderback airborne within 10 minutes. To assist the rescue on the surface, the USCG buoy tender ''Bramble'' with medical personnel on board was launched as well. Two

SA-16 The 9K38 Igla (russian: Игла́, "needle", NATO reporting name SA-18 Grouse) is a Russian/Soviet The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of E ...

amphibious aircraft An amphibious aircraft or amphibian is an aircraft (typically fixed-wing) that can take off and land on both solid ground and water, though amphibious helicopters do exist as well. Fixed-wing amphibious aircraft are seaplanes ( flying boats ...

from the

Ramey AFB Ramey may refer to: *Ramey Air Force Base, a former base in Aguadilla, Puerto Rico *Ramey, Pennsylvania * Ramey, Puerto Rico, a US sub-orbital launch site * Ramey House, an historic mansion in Tyler, Texas, USA People * Ramey Dawoud, Sudanese Amer ...

located at the far NW corner of Puerto Rico were also dispatched. Together they were able to rescue twelve passengers and all five crew members from the rough seas. LCDR Bilderback's PBY had 15 survivors on board when it found itself in a dire situation: because of the missing

APU APU or Apu may refer to: Film and television * ''The Apu Trilogy'', a series of three Bengali films, directed by Satyajit Ray, with the fictional character Apu Roy, comprising: ** ''Pather Panchali'' (''Song of the Little Road'') (1955), the first ...

and bilge pump the flying boat had taken on a lot of sea water and almost no power left to takeoff. The decision was made to transfer the survivors to the ''Bramble''. Sea conditions worsened and after the successful transfer of all but two teenage survivors LCDR Bilderbeck's only options were to either abandon the flying boat or to attempt to

taxi A taxi, also known as a taxicab or simply a cab, is a type of vehicle for hire with a driver, used by a single passenger or small group of passengers, often for a non-shared ride. A taxicab conveys passengers between locations of their choice ...

it back on the sea to San Juan Harbor. As they passed Fort ''El Morro'' and taxied into San Juan Harbor, people lined the shore cheering the rescuers.

Probable cause

The following causes were found by the investigation: * inadequate maintenance: engine no. 3 was not changed, leading to its failure immediately subsequent to take-off. * faulty engine parts * the pilots' attempt to re-establish a climb without using all available power after the loss of the second engine (engine no. 4). This led to a nose high pitch attitude and rapid decrease of

airspeed In aviation, airspeed is the speed of an aircraft relative to the air. Among the common conventions for qualifying airspeed are: * Indicated airspeed ("IAS"), what is read on an airspeed gauge connected to a Pitot-static system; * Calibrated a ...

which settled the aircraft at an altitude too low for an effectual recovery. In subsequent legal proceedings Captain Burn was exonerated and the fault turned out to be inadequate maintenance and faulty parts.

Aftermath

* After this accident it was recommended to brief the passengers about the location and usage of emergency exits and

personal flotation device A personal flotation device (PFD; also referred to as a life jacket, life preserver, life belt, Mae West, life vest, life saver, cork jacket, buoyancy aid or flotation suit) is a flotation device in the form of a vest or suite that is worn by a ...

s before flights over open water. * In memory of the lives lost and honoring the rescuers a San Juan resident wrote a ballad. * LCDR Bilderback was awarded his second

Air Medal The Air Medal (AM) is a military decoration of the United States Armed Forces. It was created in 1942 and is awarded for single acts of heroism or meritorious achievement while participating in aerial flight. Criteria The Air Medal was establish ...

. His co-pilot LCDR Jack Natwig received the

Silver Lifesaving Medal The Gold Lifesaving Medal and Silver Lifesaving Medal are U.S. decorations issued by the United States Coast Guard. The awards were established by Act of Congress, 20 June 1874; later authorized by . These decorations are two of the oldest med ...

for jumping into the sea to successfully rescue a young boy. Air Crew members Bill Pinkston, Jim Tierney, Peter Eustes and Raymond Evans were all commended by the Commandant of the USCG for a job well done. * Pan Am reused the name ''Clipper Endeavor'' for both a Boeing 707-321B in 1962 and a Boeing 727-235 in 1980. A

Douglas DC-7B The Douglas DC-7 is an American transport aircraft built by the Douglas Aircraft Company from 1953 to 1958. A derivative of the DC-6, it was the last major piston engine-powered transport made by Douglas, being developed shortly after the ea ...

was named Clipper Endeavour.

References

External links

Report
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Civil Aeronautics Board The Civil Aeronautics Board (CAB) was an agency of the federal government of the United States, formed in 1938 and abolished in 1985, that regulated aviation services including scheduled passenger airline serviceStringer, David H."Non-Skeds: Th ...

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Accident Description Pan Am Flight 526A
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Accident Description Pan Am Flight 526A''PanAmAir.org''
{{DEFAULTSORT:Pan Am Flight 0526a 1952 in Puerto Rico Aviation accidents and incidents in 1952 Airliner accidents and incidents in Puerto Rico Airliner accidents and incidents involving ditching 526A Accidents and incidents involving the Douglas DC-4 April 1952 events in North America Aviation accidents and incidents in the United States in 1952 Airliner accidents and incidents caused by engine failure