Allegheny Airlines Flight 853

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Allegheny Airlines Flight 853
Accident
DateSeptember 9, 1969
SummaryMid-air collision
SiteMoral Township, Shelby County, near Fairland, Indiana, U.S.
39°37′02″N 85°55′14″W / 39.61722°N 85.92056°W / 39.61722; -85.92056Coordinates: 39°37′02″N 85°55′14″W / 39.61722°N 85.92056°W / 39.61722; -85.92056
Total fatalities83 (all)
Total survivors0
First aircraft
Allegheny DC-9 (6962228132).jpg
An Allegheny Airlines DC-9-31 sister ship of N988VJ, 1977
TypeMcDonnell Douglas DC-9-31
OperatorAllegheny Airlines
RegistrationN988VJ
Flight originBoston Logan Airport
1st stopoverGreater Cincinnati Airport
2nd stopoverIndianapolis International Airport
DestinationSt. Louis International Airport
Passengers78
Crew4
Fatalities82 (all)
Survivors0
Second aircraft
43 Air School Piper PA-28-140 ZS-PGS (23770001315).jpg
A Piper PA-28 similar to the accident aircraft
TypePiper PA-28-140
OperatorPrivate
RegistrationN7374J
Passengers0
Crew1
Fatalities1 (all)
Survivors0

On September 9, 1969, Allegheny Airlines Flight 853, a McDonnell Douglas DC-9 passenger jet, collided in mid-air with a Piper PA-28 light aircraft near Fairland, Indiana, United States. The DC-9 was carrying 78 passengers and 4 crew members. The Piper was leased to a student pilot on a solo cross-country flight. All 83 occupants of both aircraft were killed in the accident and both aircraft were destroyed by the collision and ground impact.[1]

Flight history[edit]

Allegheny Airlines Flight 853, a DC-9-31, registration N988VJ,[2] was a regularly scheduled flight departing Boston, Massachusetts, for St. Louis, Missouri, with stops in Baltimore, Cincinnati and Indianapolis. Captain James Elrod (47) and First Officer William Heckendorn (26) were at the controls. Elrod was a seasoned veteran, with more than 23,800 flight hours. The young co-pilot had accumulated close to 3,000 flight hours.[1] The flight departed Cincinnati at 3:15pm en route to Indianapolis. Allegheny 853, flying under Instrument Flight Rules (IFR) clearance to Indianapolis, was instructed by Indianapolis Approach Control to descend to 2500 feet after passing the Shelbyville VOR at 6000 feet. The flight was then vectored to a 280 degree heading.[1]

Meanwhile, the private Piper PA-28, registration N7374J,[3] piloted by Robert Carey (34), was on a southeasterly heading. It was operating under a filed visual flight rules (VFR) flight plan which indicated a cruising altitude of 3500 feet. The PA-28 was not in communication with Air Traffic Control, and was not transponder equipped,[4] and there was no evidence it appeared as a primary radar target on the radarscope.[1]

The two aircraft converged at a relative speed of 350 miles per hour. The initial point of impact, as determined by the NTSB, was at the top front right section of the DC-9's vertical stabilizer, just underneath the horizontal stabilizer. On the Piper, the impact point was on the front left side of the plane, just forward of the left wing root.[5]. The impact severed the entire tail assembly of the DC-9, which inverted and plowed into a soybean field at an approximate speed of 400 miles per hour, about a hundred yards north of the Shady Acres mobile home park. [6]

Probable cause[edit]

The National Transportation Safety Board in a report adopted July 15, 1970, released the following Probable Cause:[1]

The Board determines the probable cause of this accident to be the deficiencies in the collision avoidance capability of the Air Traffic Control system of the Federal Aviation Administration in a terminal area wherein there was mixed instrument flight rules (IFR) and visual flight rules (VFR) traffic. The deficiencies included the inadequacy of the see-and-avoid concept under the circumstances of this case; the technical limitations of radar in detecting all aircraft; and the absence of Federal Aviation Regulations which would provide a system of adequate separation of mixed VFR and IFR traffic in terminal areas.

Legacy[edit]

After this and similar mid-air collisions and near misses, both the NTSB and FAA realized the inherent limitations of the "see and be seen" principle of air traffic separation in visual meteorological conditions, especially when aircraft of dissimilar speeds or cloud layers and other restrictions to visibility are involved.[1] The following corrective steps have since been taken:

  • Transponders are now installed in most general aviation aircraft[7] and all commercial/air-carrier aircraft, dramatically increasing radar visibility of lower and slower-flying smaller aircraft, especially near atmospheric disturbances or other clutter (see Air Traffic Control Radar Beacon System and Secondary Surveillance Radar)
  • Most airports with scheduled airline service now have a surrounding controlled airspace (ICAO designation Class B or Class C) for improved IFR/VFR traffic separation - all aircraft must be transponder equipped and in communication with ATC to operate within this controlled airspace[8]
  • Most commercial/air-carrier aircraft (and some general aviation) now have an airborne collision avoidance or TCAS device on board, that can detect and warn about nearby transponder-equipped traffic[7]
  • ATC radar systems now have "conflict alert" - automated ground-based collision avoidance software that sounds an alarm when aircraft come within less than a minimum safe separation distance[9]

See also[edit]

References[edit]

  1. ^ a b c d e f Aircraft Accident Report, Allegheny Airlines, Inc., DC-9, N988VJ, and a Forth Corporation, Piper PA-28, N7374J, Near Fairland, Indiana, September 9, 1969 (PDF). National Transportation Safety Board. July 15, 1970. NTSB-AAR-70-15. Retrieved March 25, 2016.
  2. ^ "FAA Registry (N988VJ)". Federal Aviation Administration.
  3. ^ "FAA Registry (N7374J)". Federal Aviation Administration.
  4. ^ "Death in the Skies" - Time magazine article Archived May 5, 2005, at the Wayback Machine.
  5. ^ http://www.allegheny853.net/69story.htm
  6. ^ http://www.allegheny853.net/69story.htm
  7. ^ a b FAA Statistics, 2005 Archived March 3, 2016, at the Wayback Machine.
  8. ^ FAA Federal Aviation Regulations
  9. ^ NTSB Conflict Alert Safety Recommendation, 2003

 This article incorporates public domain material from websites or documents of the National Transportation Safety Board.

External links[edit]