Prinair Flight 277
Puerto Rico… de Havilland DH1142 · Controlled flight into terrain caused by ATC error
From Cyril E. King Airport (STT) to Luis Munoz Marin International Airport (SJU)
Event
- Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
- Accident
- InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
- Unknown
- Event fatalities
- 19 · all aircraft and ground
- Ground fatalities
- 0
- Occupants
- Unknown
- Survivors
- 0
- InjuriesFatal: death within 30 days. Serious: over 48 hours in hospital within a week, most broken bones, severe bleeding, nerve or organ damage, or serious burns. Minor: anything less. Glossary
- 0 serious · 0 minor (NTSB)
- OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
- Airline
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Visual Meteorological Cond
de Havilland DH1142
- Aircraft type
- de Havilland DH1142
- Category
- Airplane
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- N563PR
- Operator
- Puerto Rico…
- Onboard fatalities
- Unknown
- Route
- From Cyril E. King Airport (STT)To Luis Munoz Marin International Airport (SJU)
- Aircraft age
- Not recorded
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 121: Air carrier (scheduled domestic passenger service)
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- En route · cruise
- Defining eventThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- Controlled collision with ground/water
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Destroyed
Cause areas
- Personnel › Issued improper or conflicting instructions
- Personnel › Other
Approximate · Coordinates from the Wikipedia article; not checked against an investigation report.
From the Wikipedia article
Prinair Flight 277 was a regular passenger flight by Puerto Rican airline Prinair, between Harry S. Truman Airport in Charlotte Amalie, U.S. Virgin Islands, and Isla Verde International Airport in Carolina, Puerto Rico, a suburb of San Juan. On March 5, 1969, the flight, operated by a de Havilland Heron 2D N563PR, crashed into a mountain near Fajardo, killing all 19 occupants on board.
Flight
Prinair Flight 277 left Charlotte Amalie at 5:15 p.m. on Wednesday, March 5, 1969, for a short flight to the San Juan area's main airport in Carolina. It was an uneventful flight until the airplane entered mainland Puerto Rico. This was the point in which the airplane's pilot contacted San Juan's approach control, letting them know that they were flying at 4000 ft and maintaining that flight level.
Then, the airport's approach controller responded with, "Prinair two seven seven San Juan Approach Control radar contact three miles east of Isla Verde fly a heading of two five zero for a vector to ILS final maintain four thousand." The approach controller, who was a trainee on the fateful afternoon, mistakenly thought that Prinair Flight 277 was near San Juan, but it was instead near Luquillo at what is described as the "Fajardo intersection". One minute after this communication, Prinair Flight 277 was asked to go to flight level 3, or 3,000 ft and prepare for landing. The airplane was vectored for a landing into runway 7. The plane's pilots, trusting that the information given to them was correct, followed the instructions and prepared for landing, soon finding themselves in front of an unavoidable mountain instead. At 5:38 pm, 23 minutes after the flight took off from St. Thomas, it crashed into some trees on the Sierra Luquillo mountains, killing everyone on board.
Investigation and cause
Investigation
An NTSB investigation that followed discovered that this accident would not have been survivable in any way. The controller's home and belongings were investigated as part of the investigation and it was found he had a typical family life, along with some of the furnishings and electrical objects found at a typical family house.
On March 17, 1969, the controller revealed to investigators, that 3 years before, a flight surgeon had sent him to see both a psychiatrist and a psychologist, and that on March 5, the day of the accident, he was feeling very tense and anxious.
It was noted also that the accident area had several peaks that were over 3,000 ft and that the weather conditions during that day would have prevented the pilots from seeing the peaks ahead of them.
The controller's erroneous indications meant he thought the aircraft was 10 mi further west than it actually was. About 5:33 p.m., or five minutes before the crash, the flight coordinator's supervisor ordered him to go perform other duties, and then proceeded to give the controller's instructor instructions to go and do collateral duties. By then, the controller was directing 5 flights, including Prinair Flight 277. Some pilots on these five flights were heard complaining because the instructor's own transmissions were interrupting the controller's.
Several other key elements were discovered by the investigation.
Text from the Wikipedia article “Prinair Flight 277” (revision 1363154877, retrieved 2026-09-18) by its authors, under CC BY-SA 4.0. Extracted as plain text: references, tables, images and some sections are left out. Read the article
NTSB remarks
ACFT UNDER RADAR CTL.VECTORED INTO MT BY CONTROLLER TRAINEE WHO WAS NOT ADEQUATELY SUPERVISED.
NTSB's remark from its 1962–1981 archive, as recorded (abbreviated, at most 98 characters): the archive has no narrative
Sources
Wikipedia article: Prinair Flight 277
- Article
- Prinair Flight 277
- Revision
- 1363154877 · 2026-07-08 · retrieved 2026-09-18
- Wikidata
- Q20715028
- Licence
- Text CC BY-SA 4.0, by the article's authors; Wikidata CC0; town positions GeoNames (CC BY 4.0)
NTSB record
- Event ID
- 19690305P030941
- Case number
- Unknown
- Dataset
- historical-pre1982
- Source SHA-256
- abe1a933b4b73583d61684309f7f0610c281e3c1de3537c6471bf2a98ba6481d
Where each value comes from
- Record
- Wikipedia article "Prinair Flight 277" (page 47118058, revision 1363154877); merged with NTSB case NTSB19690305P030941 (PRE1982 tblFirstHalf (one row per aircraft, grouped by date, place and time))
- Date
- NTSB record NTSB19690305P030941: PRE1982 DATE_OCCURRENCE
- Place and country
- Wikipedia infobox: site; country from NTSB record NTSB19690305P030941
- Map position
- Wikipedia: Wikipedia article coordinates
- Aircraft, operator and route
- NTSB record NTSB19690305P030941: PRE1982 REGIST_NO, ACFT_MAKE, ACFT_MODEL; gaps from Wikipedia infobox: aircraft type, registration, operator, origin and destination; route airports from the linked airport articles' Wikidata codes (OurAirports)
- Operation
- NTSB record NTSB19690305P030941: operated under Part 121: Air carrier (scheduled domestic passg.svc)
- Fatalities
- NTSB record NTSB19690305P030941: PRE1982 TOTAL_ABRD_FATAL of each aircraft, plus people on the ground and others outside the aircraft
- Ground fatalities
- NTSB record NTSB19690305P030941: events.inj_f_grnd
- Summary
- Wikipedia infobox: summary
Source notes (4)
- One occurrence in two sources, merged: the Wikipedia article "Prinair Flight 277" and NTSB case NTSB19690305P030941, matched by the same aircraft registration and date. For this US event the NTSB's values are used where the two differ; each value names its source.
- From NTSB's 1962-1981 archive (PRE1982), which holds at most a short remark (98 characters, abbreviated) instead of a narrative; the accident type, phase of flight, causes and conditions are NTSB's codes, decoded as the archive defines them.
- Reviewed means this record passed the site's consistency check, not that it was checked against a narrative or report - there is none to check against.
- The operation category is mapped from the archive's operator and operation codes and has not been reviewed.