All fifty passengers and five crew members on board the aircraft died, making this the deadliest disaster in Danish aviation history.

Throughout its life it had changed owners several times with different registrations (N73128, EC-FDP, PK-GDS, HR-SAX, JA101C, N770PR, and C-GKFT), undergone various modifications,[3][4] and had been rebuilt after a landing accident in 1978.

[4] In addition, the aircraft was not originally equipped with an auxiliary power unit (APU), but one was later added as an aftermarket modification and is relevant to this incident.

The flight crew consisted of Captain Knut Tveiten and First Officer Finn Petter Berg, both aged 59.

[3] Before the flight, the Partnair crew found that one of LN-PAA's two main power generators was defective and had been so since 6 September.

[4] The minimum equipment list was not updated to reflect the addition of an auxiliary power unit (APU), however, Berg decided that he would run the APU throughout the flight so that the plane would have two sources of power after reviewing the minimum equipment list of a comparable aircraft and the emergency checklist.

[8] As Flight 394 neared the Danish coastline, 22,000 feet over the North Sea, Copenhagen air traffic control saw that the plane was off course and falling quickly, appearing to crash into the sea, roughly 20 kilometres (11 nautical miles) north of the Danish coast.

The pieces had settled over an area two kilometres (1+1⁄4 mi) wide, leading the investigators to believe that LN-PAA disintegrated in the air.

[3] Speculation in the press later included a scenario where the plane had been shot down, possibly by the NATO war exercise "Operation Sharp Spear", which took place on the day of the accident flight near the flight path, as investigators had found small traces of high explosives on parts recovered from the sea bed.

Investigators concluded that the aircraft pieces acquired residue from the bottom of the sea or that the traces of explosives were accumulated from contamination before the accident or due to storage.

This led the AIBN to conclude that the unidentified objects tracked at high altitude by Swedish radar for 38 minutes were likely the shroud doors, which had separated from the aircraft tail.

[3][4][page needed] The Convair’s flight data recorder (FDR) was an antiquated analog model that used metal foil strips scratched by moving pins.

[4][page needed] One needle recorded some lines twice, initially confusing the investigators, leading the team to send the FDR to Fairchild Industries who manufactured it.

[3] The manufacturer asked an ex-employee, the highest expert regarding the company's FDRs, to temporarily leave retirement to examine the recorder.

The expert concluded that the needle supposed to have been recording the altitude had been shaking so much that it left other stray marks on the foil.

A review of the maintenance records of the aircraft revealed that during the overhaul, the mechanic discovered wear on one of the four bolts that held the vertical fin and fuselage together and replaced it.

Mary Schiavo, the Inspector General of the United States Department of Transportation from 1990 to 1996, oversaw investigations leading to over 150 criminal convictions and over $47 million in restitutions and fines under the Suspected Unapproved Parts (SUP) program.

The accident was featured in season seven of the internationally distributed Canadian made documentary series, Mayday, in the episode entitled "Blown Apart".