Aircraft Accident Report Northeast Airlines, Inc
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SA-408 FILE NO. 1-0024 AIRCRAFT ACCIDENT REPORT NORTHEAST AIRLINES, INC. FAIRCHILD HILLER FH-227C1 N380NE NEAR HANOVER, NEW HAMPSHIRE OCTOBER 25, 1968 ADOPTED: APRIL 1, 1970 NATIONAL TRANSPORTATION SAFETY BOARD Bureau of Aviation Safety Washington, 0. C. 20591 ~~ For sale by Clearinghouse for Federal Scientific and Technical Informatlon, U.S. Deputment Of Commerce, Springeeld, Yn. 22151. Annual Subscription price $12.00 Domestic; $15.00 Foreign; single copy $3.00; hmroflche $0.65. Report Number: NTSB-AAR-70-7 NORTHEAST AIRLINES. INC . FAIRCHILD HILLER FA.227C. N38ONE NEAR HANOVER. m HAMPSHIRE OClWBE3 25. 1968 TABLE OF CONTENTS Page synopsis ..................... 1 Frobable Cause .................. 1 1 . Investigation .................. 2 1.1 History of the Flight .............. 2 1.2 Injuries to Persons ............... 4 1.3 Wage to Aircraft ................ 4 1.4 Other mge................... 4 1.5 Crew Inrormation ................. 4 1.6 Aircraft Information ............... 4 1.7 Meteorological Information ............ 4 1.8 Aids to Navigation ................ 7 1.9 Communications .................. 9 1.10 Aerodrome and Ground Facilities ......... 9 1.11 Flight Recorders ................. 9 1.12 Wreckage ..................... 11 1.13 Fire ....................... 1-3 1.14 Survival Aspects ................. 1.15 Tests and Research ................ Flight Tests .................. Radio Interference Meaeurements ........ Other VOR Interference Studies ......... Tests at Wilcox Electric, Kansas City. Missouri . 17 Northeast Airlines Tests ............ 18 2 . Analysis and Conclusions ............. 2.1 Analysis ..................... 2.2 Conclusions ................... (a) Findings ................. (b) Probable Cause .............. 3. Recommendations ................. 4. Appendices A . Investigation and Hearing 1. Investigation 2. Hearing 3. Preliminary Report B . Crew Information C . Aircraft Information D. Course Needle Oscillations on VHF Omnidirectional Range (VOR) Receivers E. Omni Bearing Indicator F. Letter to Mr. David D. Thomas from Joseph J, O'Connell, Jr., Chairman - dated October 29, 1968 Letter to Chairman Joseph J. O'Connell, Jr., from D. D. Thomas, dated November 7, 1968 Letter to Honorable David D. Thomas from Chairman O'Connell dated December 13, 1968 Letter to Chairman O'Connell from D. D. Thomas, dated January 14, 1969 G. Approach Chart - Lebanon, N.H. ii SA-408 File No. 1-0024 NATIONAL TRANSPORMTION SAFETY BOARD DEPARWNT OF TRANSFORTATION , Jr., AIRCRAFT ACCIDENT REPORT B Thomas, Adopted: April 1, 1970 NORTHEAST AIRLINES, INC. me11 FAIRCHILD HILLER FH-227C, N380NE NEAR HANOVEFi, NEW HAMPSHIRE OCTOBER 25, 1968 SYNOFSIS A Northeast.~.- air .~. .. lines,^ b.2.., -.--Fairchild Hiller FH-227C~.. ~-t N~~ONE, crashedmproximately 1817 e.d.t., October 25, 1968, near Ranover, New Hampshire. The aircraft, Flight 946, had been cleared for an approach to the Lebanon Regional Airport, West Lebanon, New Rampshire, at 1808. The aircraft crashed 3.8 nautical miles northeast of the VOR station at an altitude of approximately 2,237 feet m.s.1. At this point in a standard instrument approach, the aircraft should have been no lower than 2,800 feet m.s.1. Witnesses on the ground and survivors of the accident reported that thew&atantog was shrouded in cloud or fog at the time of the accident. Of the 39 passengers and three crewmembers aboard the aircraft, nine passengers and one crewmember, the stewardess, survived the accident. The aircraft was destroyed by impact and postimpact fire. The Board determines that the probable cause of this accident was the premature initiation of a descent towa&..the~~Minimum Descent _Altitude,_.-- based on navigational instrument indications of an impending station passage in an area of course roughness. The crew was not able to determine accurately its position at this time because they had performed a nonstandard i_nstrume&_amroach and there were noO.supple- mental navigational aids available for their use. __. .~ As a result of the investigation of this accident, the Board forwarded recommendations to the Federal Aviation Administration con- cerning the operating characteristics of the Lebanon VOR and their relationship with airborne navigation receivers and instrumentation. The Administrator indicated he had taken or pl8nned actions which were basically in accord with the intent of the Board’s recommendations. -2- 1. INVESTIGATION 1.1 History of the Flight A Northeast Airlines, kc., Fairchild Hiller FH-227C, N~~ONE, crashed at approximately 1817 e.d.t., October 25 , 1968, near Hanover, New Hampshire. The aircraft was being operated in scheduled domestic passenger service as Flight 946 from Boston, Massachusetts, to Montpelier, Vermont, with an en route stop at Lebanon, New Hampshire. Of the 39 passengers and three crewmembers aboard the aircraft, nine passengers and one crewmember, the stewardess, survived the accident. The aircraft was destroyed by impact and postimpact fire. Flight 946 departed from Boston at 1742 and was cleared to Lebanon, Mew Hampshire. The flight was cleared to proceed in accord- ance with a flight plan which called for a cruising altitude of 8,000 feet m.s.1. and an estimated time en route of 33 minutes at an estimated airspeed of 245 knots. The original scheduled departure time of 1655 was not met due to a delay in getting the aircraft to the gate for passenger loading. The flight was reported to be normal and routine, and was ob- served on radar, until it reached a point reported by the radar controller to be 2.5 nautical miles (NM) south-southeast of the Lebanon VOR. The flight was cleared, at 1808, for an approach to the Lebanon Airport to cruise at 5,000 feet and report leaving 6,000 feet. At 1810:45, the controller advised the crew that radar service had been terminated and the flight was cleared to contact the Lebanon Flight Service Station. At 1811, the crew 2 contacted the Lebanon Flight Service Station, reported that they were'SIA" (Standard Instrument Approach), and re- quested the Lebanon weather. They were advised that the Lebanon weather was an estimated ceiling of 2,000 feet overcast; visibility was.10miles; there were breaks in the overcast; the altimeter setting was 29.55; and the wind was calm. They were also advised that Runway two five was in use and there was no other reported traffic. The crew acknowledged this information and there were no further recorded trans- missions from the crew. 1/ All times herein are eastern daylight, expressed on the 24-hour clock, unless otherwise noted. All mice communications from the flight were identified as having been made by the first officer. -3- Two surviving passengers stated that they observed the ground and clouds shortly before the first impact. The remainder of the survivors, including the stewardess, either did not look out or could not, because of their positions, see out the cabin windows. One passenger stated that ". As we approached Lebanon, the cloud cover had been gradually thinning and before we began ow descent, ground had been visible in patches between the clouds for several minutes. On the early part of the descent, the ground continued to be visible. After the turn to the final approach, with the wheels down, we were flying between two nearly vertical cloud banks in the gentle smooth descent which I described in my prior statement. There was no cloud directly below us and the level of the base of the clouds at this point was slightly below the level of the aircraft so that the ground was clearly visible under the cloud to a substantial distance ahead and to the side. I was looking out and observed a pond and that the terrain had very few roads and no houses. "As we continued ow descent, I continued to observe and watched the slope of the ground rising ahead of us at about twenty degrees in the direction of flight. We were so near the ground at this time that I could clearly see the individual trees which appeared fist size and began to look ahead in the direction of flight for airport approach lights as I assumed that we must be very near the touch down point. I observed the rising ground until I suddenly lost all visibility as we had entered a cloud. "After a few seconds in the cloud, I felt the initial impact which was gentle and seemed no more severe than a normal touch down. I do not remember any severe impact. "There was no change in course, speed, bank angle, descent angle or engine sound from the time the aircraft completed its turn and started its gradual descent until impact. .11 Most of the survivors described the impact as "smooth," "not a crash but more as settling," "a rough landing," etc. A ground witness, south of the accident site, heard the aircraft approaching. When he looked toward the sound, he saw the "slightly fog covered mountain," but did not see the aircraft until the landing lights appeared in the fog. A few seconds later, the aircraft crashed into the mountain. He reported the accident to the Federal Aviation Administration (FAA) Flight Service Station (FSS) at approximately 1836. Other ground witnesses stated that shortly after the accident, the mountaintop was clearly visible. The accident occurred approximately 1 minute before the end of Civil twilight. -4- The accident site was located at longitude 72"8'.7 west and latitude 43"43'.3 north, at an elevation of approximately 2,237 feet m.s.1. This location was approximately 3.8 NM northeast of the Lebanon VOR and 8.2 NM northeast of the Lebanon Airport. 1.2 Injuries to Persons Injuries -Crew Passengers Other Fatal 2 30 0 Nonfatal 1 9 0 None 0 0 1.3 hmage to Aircraft The aircraft was destroyed by impact and postimpact fire. 1.h Other Damage None other than destruction to trees in the accident area. 1.5 Crew Information The crew was properly certificated and qualified in accordance with the existing FAA regulations. (For details see Appendix B.) 1.6 Aircraft Information According to the company records, the aircraft was airworthy at the time of departure from Boston and it had been maintained in accord- ance with the applicable FAA and company regulations.