Bell 412SP N78S
4 April 1991 · Merion, Pennsylvania, United States · Fatal
Summary
On 4 April 1991 at about 17:10 local time, a Bell 412SP registered N78S, operated by Sun Company Inc., was involved in an accident near Merion, Pennsylvania, United States. 12 people were on board and 5 died. 2 people on the ground also died. The aircraft was destroyed. The NTSB has published a probable cause for this accident; it is quoted in full below.
The record
- Date
- at 17:10
- Classification
- Accident
- Location
- Merion, Pennsylvania, United States
- Coordinates
- 39.9996, -75.2409
- Aircraft
- Bell 412SP
- Registration
- N78S
- Category
- Helicopter
- Engines
- 2
- Operator
- Sun Company Inc.
- Operating rule
- Part 91: General Aviation
- Purpose of flight
- Executive/Corporate
- Phase of flight
- Not recorded
- Route
- Philadelphia → Radnor
- Aircraft damage
- Destroyed
- Weather
- VMC
- Light
- Day
- NTSB number
- DCA91MA031
People
5 people died, including 2 on the ground.
| On board | Died | Serious | Minor | Uninjured | On the ground |
|---|---|---|---|---|---|
| 12 | 5 | 0 | 0 | 0 | 2 |
Probable cause
THE POOR JUDGEMENT BY THE CAPTAIN OF THE AIRPLANE TO PERMIT THE IN-FLIGHT INSPECTION AFTER HE HAD DETERMINED TO THE BEST OF HIS ABILITY THAT THE NOSE LANDING GEAR WAS FULLY EXTENDED, THE POOR JUDGMENT OF THE CAPTAIN OF THE HELICOPTER TO CONDUCT THE INSPECTION, AND THE FAILURE OF THE FLIGHTCREW OF THE HELICOPTER TO MAINTAIN SAFE SEPARATION.
Quoted verbatim from the NTSB record. This site does not paraphrase or interpret it.
Read the full NTSB narrative
PIPER AEROSTAR 601, N3645D, WAS ARRG AS BELL 412 (HELICOPTER), N78S, WAS DEPG. N3645D RPRTD THE ACFT'S NOSE GEAR INDCR LGT DID NOT ILLUMINATE TO VERIFY THE NOSE GEAR WAS DWN & LOCKED. CREW OF N78S HEARD THE COM & SAW N3645D AS THEY CROSSEDBENEATH N3645D'S APCH PATH. THEY RPRTD N3645D'S NOSE GEAR APPEARED TO BE EXTDD. N3645D FLEW PAST THE TWR & TWR PSNL ALSORPRTD THE NOSE GEAR APPEARED TO BE EXTDD. AS N3645D WAS CLRD TO TURN DWNWND, N78S OFFERED TO JOIN FOR A CLOSER LOOK. CAPT OF N3645D ACCEPTED THE OFFER. DRG JOINUP, N78S CONVERGED FM LEFT REAR, THEN RPRTD THEY WOULD PASS ARND THE RGT SIDE& LOOK AT EVERYTHING AS THEY WENT BY. THEY RPRTD THAT EVERYTHING LOOKED OK. MOMENTS LTR, THE 2 ACFT COLLIDED & CRASHED TO THE GND. NO MECH RSN WAS FND THAT WOULD HAVE RESULTED IN THE ACDNT. NONE OF THE PLTS HAD TRNG FOR FLT IN CLOSE PROX- IMITY TO ANOTHER ACFT. THERE WERE INDCNS THE CAPT OF N3645D LACKED TRNG IN ACFT SYSTEMS & THAT HIS EMPLOYER (THE OPER) LACKED SURVEILLANCE BY THE FAA. THE EMERG PROC SXN OF THE AEROSTAR FLT MANUAL LACKED INFO ON EMERG GEAR EXTN.
Quoted verbatim from the NTSB record.
Aircraft involved
| Aircraft | Registration | Operator | Damage |
|---|---|---|---|
| Bell 412SP 412SP | N78S | Sun Company Inc. | Destroyed |
| Piper AEROSTAR 601 AEROSTAR 6 | N3645D | Lycoming Air Service | Destroyed |
Other Bell 412 accidents
| Date | Aircraft | Location | Operator | Outcome | Died |
|---|---|---|---|---|---|
| 26 Aug 1991 | Bell 412 | Garden Banks | Petroleum Helicopters | Fatal | 1 |
| 8 Aug 1991 | Bell 412 | Rowan Midland | ERA Aviation Inc. | No injuries | - |
| 1 Jul 1991 | Bell 412 | Grand Junction, Colorado, United States | Air Methods Corporation | No injuries | - |
| 3 Nov 1990 | Bell 412 | Knoxville, Tennessee, United States | - | No injuries | - |
| 3 Dec 1993 | Bell 412 | Cameron, Louisiana, United States | - | Minor injuries | - |
| 31 Mar 1993 | Bell 412 | Topanga, California, United States | Los Angeles County Fire Dept | Unknown | - |
Other accidents in this area
| Date | Aircraft | Location | Operator | Outcome | Died |
|---|---|---|---|---|---|
| 4 Jul 1991 | Piper PA-22-150 | Tunkhannock, Pennsylvania, United States | Skyhaven Airport, Inc. | Minor injuries | - |
| 16 Jun 1991 | Boeing 747-400 | Philadelphia, Pennsylvania, United States | KLM Royal Dutch Airline | Serious injuries | - |
| 9 Jul 1991 | Waco UPF-7 | Stebensville, Pennsylvania, United States | Kriss Alan Kliegle | Minor injuries | - |
| 28 Jul 1991 | Piper PA-22-150 | Thomasville, Pennsylvania, United States | Richard Miller | No injuries | - |
| 6 Aug 1991 | Cessna 150J | Burgettstown, Pennsylvania, United States | John H Galicic | No injuries | - |
| 12 Aug 1991 | Piper PA-38-112 | Butler, Pennsylvania, United States | Beaver Aviation Service Inc. | No injuries | - |