1951 — Aug 24, United 615 crash in fog on SE approach to Oakland IAP, Decoto, CA–all 50
–50 AirDisaster.com. Accident Database. Accident Synopsis 08241951.
–50 Aviation Safety Network, Accident Description, United Flight 615, August 24, 1951
–50 CAB AIR. United Air Lines, Inc., Near Oakland, California, August 24, 1951.
–44 passengers
— 6 crew members
–50 Daily Review, Hayward, CA. “50 Die in Flaming Decoto Plane Disaster, 24 Aug 1951.
–50 Eckert. “Fatal commercial air transport crashes, 1924-1981.” AJFM&P, 3/1, Mar 1982, Table 1, p53.
Narrative Information
AirDisaster.com: “The aircraft crashed on approach to Oakland after the Captain attempted to land using visual references in foggy, misty conditions. The flight had been cleared for an instrument approach, but neither low-frequency receiver in the cockpit had been tuned to the appropriate beacon.” (AirDisaster.com. Accident Database. Accident Synopsis 08241951.)
Aviation Safety Network: “United Flight 615 departed Boston at 17:32 EST, made scheduled stops at Hartford, Connecticut, and Cleveland, Ohio, and arrived at Chicago, Illinois, at 21:59 CST. The flight departed Chicago at 22:59 CST. At 03:54, while approaching the Oakland area, Flight 615 was cleared to the Newark, California fan marker, with instructions to descend to 6,000 feet, maintain that altitude, and contact Oakland Approach Control over Altamont.
“At 04:11, the flight reported over Stockton, California, at 9,500 feet, descending. Five minutes later they were over the Altamont Intersection. The flight was cleared by Approach Control to the Oakland radio range station to maintain at least 500 feet above the tops of the clouds. The pilot followed this contact with a request for clearance direct to Newark and a straight-in range approach. This request was granted, with instructions to maintain an altitude of 500 feet on top of the cloud layer between Altamont and Newark.
“At 04:25 Flight 615 was cleared for a straight-in approach on the southeast course of the Oakland radio range from Newark. At 04:27 the flight reported leaving Newark inbound to Oakland. This was the last radio contact.
“The aircraft descended until it struck rising mountainous terrain at 983 feet MSL, 26 feet below the crest of the hill and approximately three miles to the right of the southeast on-course signal of the Oakland radio range. The major portion of the structure hurtled over the top of the knoll, scattering on the down-slope and into a canyon beyond.
“The captain was possibly using the ADF, allowing the DC-6 to be 3 miles to the right of the intended course and about 2500 feet below the 3500 feet minimum altitude. Cloud base was at 1500 feet with patches of fog obscuring terrain….
“Follow-up / safety actions: United Air Lines required crews to operate under IFR when above an overcast.”
This was, then, the fifth worst aviation disaster in the U.S. (ASN, United 615, Aug 24, 1951)
Civil Aeronautics Board, Accident Investigation Report (File No. 1-0058):
“The Accident
“United Air Lines Flight 615 of August 23, 1951, a Douglas DC-6B, N-37550, crashed at approximately 0428 on August 24, 1951, near the top of a hill while approaching the Oakland, California, Municipal Airport for landing. The impact site was 14.8 statute miles and on a true bearing of 123 degrees from the Oakland Airport. All 44 passengers and six crew members were killed instantly and the aircraft was demolished.
History of the Flight
“Flight 615 departed Boston, Massachusetts at 1732 EST, August 23, 1951, made scheduled stops at Hartford, Connecticut, and Cleveland, Ohio, and arrived at Chicago, Illinois, at 2159 DST….The flight departed Chicago at 2259 CST with crew members Captain Marion W. Hedden, First Officer George A Jewett, Flight Engineer Mario A Durante, Assistant Chief Flight Engineer Arthur W Kessler, and Stewardesses Marilynn Murphy and LaVerne Sholes. There were 44 passengers, two of whom were infants….” [p.1.]
Investigation
“The aircraft struck in rising mountainous terrain at 983 feet MSI, 26 feet below the crest of the hill… An eye witness reported that it was on a straight course, but descending, just before impact. The descent was verified by the fact that the next hill to the south, over which the flight passed, is higher than the one struck….Evidence indicated that the ground speed upon impact was between 225 and 240 miles per hour….Parts of both altimeters were found. The captain’s altimeter indicated 930 feet, the crash site was at 983 feet MSL…. [p. 2.] The impact site was shrouded in wisps of fog….
“Instrument approach procedures for the Newark area require an aircraft on an IFR [Instrument Flight Rules, as opposed in Visual Flight Rules] flight plan to maintain an altitude of not less than 3,500 feet until it has left Newark inbound to Oakland on the southeast course of the Oakland radio range. Should the aircraft be holding at Newark on the standard race-track holding pattern to the southeast of the radio facility, the minimum IFR altitude would be 4,500 feet. Since the flight did not cancel its IFR clearance and advise Approach Control…nor had it received instructions to hold, the minimum altitude permissible until leaving Newark inbound to Oakland would therefore have been 3,500 feet….” [p. 3.]
“Analysis
“Examination of the wreckage indicated that there was no in-flight failure, likewise, maintenance records failed to reveal any discrepancies which would have caused the accident. Also, no weather conditions existed which would suggest that the aircraft encountered unusual weather phenomena. There was in indication from the flight itself that everything was other than routine.
“It should be noted that all witnesses stated the aircraft was flying at low altitude in the Newark area and reconstruction of the flight path indicated the altitude was in the neighborhood of 1,500 to 2,000 feet prior to the final, straight descent. It has been pointed out that the flight was still on an IFR flight plan at the time it crashed, and the minimum prescribed altitude prior to leaving Newark is 3,500 feet. Flight 615 was neither at least 500 feet above the top of the stratus layer nor adhering to the minimum altitude of 3,500 feet as it maneuvered awaiting clearance to Oakland. Witnesses reported that it was below, or just skirting, the lower side of the clouds.
“The aircraft was equipped with two low-frequency receivers, neither of which was tuned to the Oakland radio range station. There was no evidence to indicate which pilot was flying the aircraft. Any conclusions regarding the courses of action which they took, or why navigational facilities were not properly utilized must necessarily be conjectural.
“Had the flight been conducted in accordance with the prescribed instrument procedures, this accident would not have occurred. No terrain obstructions would have been met if the flight had been at the proper altitude. Position could have been fixed on the inbound heading had the Oakland radio range been used by the flight…. [p.4.]
“Shortly after this accident, United Air Lines made certain revisions in their Flight Operations Manual to prevent, insofar as possible, the recurrence of this type of accident. All pilots were instructed that United Air Lines flights over the top of an overcast must be conducted in accordance with IFR and must be flown not lower than the CAA approved minimum IFR flight levels….
“Findings
“On the basis of all available information, the Board finds that
….
“5. The captain failed to follow the approved procedure for a straight-in range approach from Newark to Oakland by descending below the minimum altitudes for the Newark area.
“Probable Cause
“The Board determines that the probable cause of this accident was the failure of the captain to adhere to instrument procedures in the Newark area during an approach to the Oakland Municipal Airport.” (CAB File No 1-0058)
Newspaper
Aug 24: “Decoto. — A United Airlines DC-GB Mainliner smashed into a hilltop two miles east of here early today, careened into a steep canyon and burst into flames, killing all 50 persons aboard. It was the first time one of the huge four-motored luxury-type planes had crashed. The DC-GB was placed in service only this month after settlement of a pilots’ strike.
“The plane left Boston at 6:30 p.m. yesterday, stopping at Hartford, Cleveland and Chicago. It was due to make one more stop at Oakland before ending its flight at San Francisco airport at 6 a.m.
“The .plane missed clearing the top of the hill on Ted Harvey’s ranch by only 20 feet. The ceiling was low and visibility was poor. The force of the impact was so terrific that the plane was torn to bits and fragments of bodies were strewn all over the landscape. There were 44 passengers and six crew members….
“…the plane hit the hill, two propeller blades gouging out a deep pit, then careened over the top and fell down the western slope, disintegrating as it went. When it was 400 yards down the slope, it flew off the edge of a brush-choked canyon about 500 feet deep.” (The Daily Review (Hayward, CA). “50 Die in Flaming Decoto Plane Disaster, August 24, 1951.)
Sources
AirDisaster.com. Accident Database. Accident Synopsis 08241951. Accessed at: http://www.airdisaster.com/cgi-bin/view_details.cgi?date=08241951®=N37550&airline=United+Airlines
Aviation Safety Network, Flight Safety Foundation. Database. United Airlines Flight 615 approach crash 15 miles SW of Oakland International AP, August 24, 1951. Accessed 6-23-2023 at: http://aviation-safety.net/database/record.php?id=19510824-0
Civil Aeronautics Board. Accident Investigation Report. United Air Lines, Inc., Near Oakland, California, August 24, 1951. Washington, DC: CAB, March 12, 1952, 7 pages. Accessed at: http://dotlibrary1.specialcollection.net/scripts/ws.dll?file&fn=8&name=*P%3A%5CDOT%5Cairplane%20accidents%5Cwebsearch%5C082451.pdf
Daily Review, Hayward, CA. “50 Die in Flaming Decoto Plane Disaster, 8-24-1951. At: http://www.newspaperarchive.com/PdfViewerTags.aspx?img=47011622&firstvisit=true&src=search¤tResult=2
Eckert, William G. “Fatal commercial air transport crashes, 1924-1981.” American Journal of Forensic Medicine and Pathology, Vol. 3, No. 1, March 1982, Table 1.