Crash of a Douglas DC-6 off Mobile: 46 killed

Date & Time: Feb 14, 1953 at 1710 LT
Type of aircraft:
Operator:
Registration:
N90893
Flight Phase:
Survivors:
No
Schedule:
Miami – Tampa – New Orleans
MSN:
43057
YOM:
1947
Flight number:
NA470
Location:
Crew on board:
5
Crew fatalities:
Pax on board:
41
Pax fatalities:
Other fatalities:
Total fatalities:
46
Captain / Total flying hours:
17000
Captain / Total hours on type:
4110.00
Copilot / Total flying hours:
4485
Copilot / Total hours on type:
184
Aircraft flight hours:
15994
Circumstances:
Flight 470 departed Tampa at 1543LT. Its flight plan, filed previously at Miami, specified a cruising altitude of 14,500 feet according to Instrument Flight Rules and an estimated elapsed tune of two hours for the direct 498 statute miles to New Orleans. Included among the weather data attached to the captain's copy of the flight plan was a forecast of thunder-storms attended by moderate to severe turbulence in the vicinity of New Orleans, the destination. The CAA Air Route Traffic Control cleared the flight at the 14,500-foot level direct to New Orleans. Flight 470 passed over NA-3 at its cruising altitude of 14,500 feet at 1614, estimating over NA-2 at 1642, and so reported to Radio-Tampa one minute later. At that time the flight also gave the local weather: broken clouds at 6,000 feet, broken clouds at 20,000 feet and temperature 4 degrees Centigrade. Meanwhile, Flight 917 landed at New Orleans at 1612. It reached the ramp at 1617 and at 1624, its captain sent the following message to Miami flight Control and to all company stations between New Orleans and Jacksonville, Florida, including Pensacola, Florida: "Flight 917 advises extreme turbulence all altitudes just east of New Orleans." At 1636, the captain sent the following message to the same stations: "Reference extreme conditions stop at present time severe turbulence No. 1. check (NA-1) to New Orleans weather looks better to west of New Orleans." At 1649, Flight 470 reported passing over NA-2 at 1645 at 14,500 feet, and estimated being over NA-l at 1710. It also reported, "Thunderstorms all quadrants . . ." Pensacola radio received and acknowledged this message, and advised the flight of "severe turbulence" between NA-l and New Orleans as reported by Flight 917. Flight 470 acknowledged, asked what altitude Flight 917 reported turbulence, and was informed "severe turbulence at all altitudes." Again Flight 470 acknowledged. At 1654, the flight advised Pensacola that it was reducing power because of turbulence and five minutes later requested Air Route Traffic Control clearance to descend from 14,500 feet to 4,500 feet. This was granted within a minute or so, with the provision that descent between 10,000 feet and 8,000 feet be visual. At 1703, the Flight advised Pensacola of passing through 10,000 feet, and at 1712 (recorded), advised that it had reached 4,500 feet at 1710. Pensacola repeated this message back to the flight and gave it the 1648 New Orleans special weather. This was: measured 800, overcast, visibility 10 miles, wind north-northeast 25 m.p.h., with gusts to 34, the altimeter 29.61; barometer unsteady. The flight acknowledged and there were no further radio contacts. An attempt by New Orleans at 1718 to contact Flight 470 was unsuccessful, as were subsequent attempts by several other stations, and at 1840 the Coast Guard's air-sea rescue service was alerted. Low clouds and heavy seas hampered the search both by air and sea. However, on the following day (February 15) floating debris and 17 bodies were recovered from a fairly localized area in the Gulf of Mexico at about 30 degrees 38' North Latitude and 87 degrees 46' West Longitude. This position is approximately 38 miles to the right of the aircraft's direct course and is about 20 miles southeast of Mobile Point at the easterly mouth of Mobile Bay. Two wrist watches on bodies were impact stopped at 1710LT.
Probable cause:
The Board determines that the probable cause of this accident was the loss of control followed by the in-flight failure and separation of portions of the airframe structure while the aircraft was traversing an intense frontal-wave type storm of extremely severe turbulence, the severity and location of which the pilot had not been fully informed. The following findings were pointed out:
- After passing the NA-2 check point, the flight reported thunderstorms in all quadrants,
- The flight requested and was granted clearance to descend to 4,500 feet due to turbulence,
- Its last message reported reaching 4,500 feet at 1710LT,
- The aircraft penetrated a storm system of unusual severity,
- Tornadic conditions including high winds, violent gusts, and possible waterspouts were occurring in the storm system,
- The storm's movement had not been adequately anticipated in current weather forecasts,
- Although a special Severe Weather Bulletin issued at Washington, D.C., was received by National Airlines and the Weather Bureau at Miami and New Orleans, no U. S. Weather Bureau advisory weather reports were issued to ARTC to report the unexpected development and movement of the storm to en route flights; nor did National Airlines attempt to relay this information to Flight 470,
- Flight 470 entered the storm system without full knowledge of its severity,
- The aircraft's structure failed at a moment when, in all probability, gusts loads combined with violent maneuvering loads were being imposed to maintain or regain control,
- The main wreckage was located in the Gulf of Mexico 3.8 miles offshore and about 52 miles to the right of course; the left wing was found 2,100 feet from the main wreckage,
- Examination of the recovered parts revealed no indication of malfunctioning control, fatigue failure, fire, explosion, or lightning strike while in flight.
Final Report:

Crash of a Douglas DC-6 in Frankfurt: 45 killed

Date & Time: Mar 22, 1952 at 1050 LT
Type of aircraft:
Operator:
Registration:
PH-TPJ
Survivors:
Yes
Schedule:
Johannesburg – Cairo – Rome – Frankfurt – Amsterdam
MSN:
43114
YOM:
1948
Country:
Region:
Crew on board:
10
Crew fatalities:
Pax on board:
37
Pax fatalities:
Other fatalities:
Total fatalities:
45
Circumstances:
The descent to Frankfurt was started in poor weather conditions with light rain, overcast at 1,500 feet and few clouds at 300 feet. The crew informed ATC about his position vertical of Staden beacon at 4,000 feet and few minutes later over Offenbach at an altitude of 2,500 feet. For unknown reason, the four engine aircraft christened 'Koningin Juliana' was too low, hit tree tops and crashed in flames in a dense wooded area located about 7 km northeast of the airport. A passenger and a crew member were seriously injured while 45 other occupants were killed.
Probable cause:
The exact cause of the accident could not be determined with certainty. However, it is possible that the crew continued the approach below the minimum descent altitude to maintain a visual contact with the ground.

Crash of a Douglas DC-6 in Elizabeth: 33 killed

Date & Time: Feb 11, 1952 at 0020 LT
Type of aircraft:
Operator:
Registration:
N90891
Flight Phase:
Survivors:
Yes
Site:
Schedule:
Newark – Miami
MSN:
43055
YOM:
1947
Flight number:
NA101
Crew on board:
4
Crew fatalities:
Pax on board:
59
Pax fatalities:
Other fatalities:
Total fatalities:
33
Captain / Total flying hours:
11901
Captain / Total hours on type:
1059.00
Copilot / Total flying hours:
3804
Copilot / Total hours on type:
941
Circumstances:
The aircraft involved arrived at New York International Airport, 2 New York, at 2233, February 10, 1952, as Flight 402 from Miami, Florida This flight was routine, with stops at West Palm Beach, Florida, and Washington, D C. A turn-around inspection at Idlewild performed, and 1911 gallons of 100/130 grade fuel added, bringing the total fuel aboard to 2,700 gallons Also, sufficient oil was added to bring the quantity of each tank to 30 gallons. At 2322 the aircraft departed Idlewild on a ferry flight to Newark with a new crew consisting of Captain W. G. Foster, First Officer C E. St. Clair, flight Engineer I. R. Shea, and Stewardess Nancy J. Taylor. The aircraft arrived at Newark Airport at 2335, from which point it was scheduled to depart at 2359 as Flight 101, non-stop to Miami, Florida. A second inspection was accomplished at Newark and the aircraft was loaded with 2,953 pounds of mail, baggage, air express, air freight, and 59 passengers, including one infant The computed take-off gross weight was 83,437 pounds, or 6,463 pounds less than the allowable gross of 89,900 pounds This weight was so distributed that the center of gravity was within the approved limits. No fuel was added at Newark. The flight was given an instrument clearance from Newark to Miami, with West Palm Beach as alternate. To this clearance was attached the pertinent weather reports which indicated, among other things, that at Newark the ceiling was 20,000 feet, thin overcast, with the entire en route weather generally clear with ceilings of 30,000 feet at Palm Beach and Miami. At 0013, February 11, Newark Control Tower gave the flight taxi clearance to Runway 24, stating the wind was south, variable at six m p.h., and altimeter 29 92. At approximately 0017 the flight advised the tower that it was ready for takeoff Take-off clearance was issued, and the controller observed the aircraft taxi into take-off position and proceed down the runway in a normal manner, becoming airborne at 0018 after a roll of approximately 3,200 feet. The climb-out appeared normal until the aircraft passed the vicinity of the Newark Range Station. Here it was observed by Control Tower personnel to lose altitude suddenly and veer slightly to the right. This sudden loss of altitude and the movement to the right are supported by statements of surviving passengers and ground witnesses. The controller then called the flight and asked if everything was all right, to which he received the following reply, "I lost an engine and am returning to the field." The time was established as 0019. The flight was immediately cleared to land on Runway 6, which clearance was at once amended to land on any runway desired No further radio contacts were made with flight. During the last radio transmission the controller observed the aircraft continue to veer to the right at a low altitude and then disappear from sight. At 0020 cower personnel observed a fire in the vicinity of Elizabeth New Jersey. It was later established that Flight 101 had crashed in Elizabeth near the intersection of Scotland Road and Westminster Avenue. The aircraft was totally destroyed by impact forces and three crew members, 26 passengers and four people on the ground were killed.
Probable cause:
The Board determines that the probable cause of this accident was the reversal in flight of No. 3 propeller with relatively high power and the subsequent feathering of No. 4 propeller resulting in a descent at an altitude too low to effect recovery. The following findings were pointed out:
- Mechanical difficulty developed during climb shortly after takeoff from Runway 24,
- No. 3 propeller reversed in flight, and No. 4 propeller was feathered,
- Under these conditions the aircraft did not maintain altitude and settled rapidly.
Final Report:

Crash of a Douglas DC-6 in Milan

Date & Time: Dec 23, 1951 at 2035 LT
Type of aircraft:
Operator:
Registration:
I-LUCK
Survivors:
Yes
Schedule:
New York – Gander – Shannon – Milan – Rome
MSN:
43215
YOM:
1950
Country:
Region:
Crew on board:
10
Crew fatalities:
Pax on board:
38
Pax fatalities:
Other fatalities:
Total fatalities:
0
Circumstances:
The crew started the approach to Milan-Malpensa in low visibility due to foggy conditions. About eight km from the runway threshold, while flying at an insufficient height, the aircraft hit the ground, lost its undercarriage and came to rest in flames in a field, broken in three. All 48 occupants were able to evacuate the cabin and three passengers were slightly injured. The aircraft was destroyed.
Probable cause:
The crew decided to continue the ILS approach below the minimum descent altitude, causing the aircraft to struck the ground.

Crash of a Douglas DC-6 in Mexico City

Date & Time: Sep 1, 1951
Type of aircraft:
Operator:
Registration:
XA-JOR
Survivors:
Yes
Schedule:
Los Angeles – Mexico City
MSN:
43211
YOM:
1950
Country:
Crew on board:
4
Crew fatalities:
Pax on board:
38
Pax fatalities:
Other fatalities:
Total fatalities:
0
Circumstances:
On final approach to Mexico City Airport, the four engine aircraft crashed in unknown circumstances in the Texcoco Lagoon, few km short of runway. All 42 occupants were rescued but the aircraft was damaged beyond repair.

Crash of a Douglas DC-6B near Union City: 50 killed

Date & Time: Aug 24, 1951 at 0428 LT
Type of aircraft:
Operator:
Registration:
N37550
Survivors:
No
Site:
Schedule:
Boston – Hartford – Cleveland – Chicago – Oakland – San Francisco
MSN:
43260
YOM:
1951
Flight number:
UA615
Crew on board:
6
Crew fatalities:
Pax on board:
44
Pax fatalities:
Other fatalities:
Total fatalities:
50
Captain / Total flying hours:
12032
Captain / Total hours on type:
417.00
Copilot / Total flying hours:
5842
Copilot / Total hours on type:
2848
Aircraft flight hours:
361
Circumstances:
Air Route Traffic Control (ARTC) cleared Flight 615 on an instrument flight plan from Chicago to Oakland, and from Oakland to San Francisco in accordance with Visual Flight Rules (VFB). Altitude was to be 18,000 feet man sea level (MSL) via Red Airway 4, Creen Airway 3, and Red Airway 6 from Chicago to Denver, direct to Milford, Utah, and thence direct to Oakland. Flight between Oakland and San Francisco was to have been via Green Airway 3 at 500 feet. Routine radio contacts were made en route. At 0354, August 24, 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, California. At 0411, the flight reported over Stockton, California, at 9,500 feet, descending. At this time the flight was given, and acknowledged, the Oakland altimeter setting of 29 88 inches. Flight 615 reported over the Altamont Intersection at 0416, and made initial contact with Oakland Approach Control one-half minute later. Clearance of the flight into Oakland was now vested in Approach Control, and no further radio contacts were made with company communications. 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. The Newark fan marker and compass locator lie on the southeast leg of the Oakland radio range This request was granted, with instructions to maintain an altitude of 500 feet on top of the cloud layer between Altamont and Newark. At 0422, the flight reported approaching the Hayward, California, compass locator, which is between Newark and Altamont, and requested a second modification to clearance instructions by asking for a straight-in ILS (Instrument Landing System) approach 2. Approach Control advised it to stand by due to another aircraft in the area. Flight 615 shortly thereafter advised Approach Control that it was approaching Newark and to disregard the request for an ILS approach. At 0425 Flight 615 was cleared for a straight-in approach on the southeast course of the Oakland radio range from Newark. At 0427 the flight reported leaving Newark inbound to Oakland. This was the last radio contact. A minute later, the four engine aircraft struck the Tolman peak (985 feet high) located about 14,6 miles southeast of Oakland Airport. The aircraft was destroyed by impact forces and all 50 occupants were killed.
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. The following findings were pointed out:
- 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,
- The flight had been cleared for a straight-in range approach, but neither receiver was tuned to the Oakland radio range station, as required,
- The aircraft struck a hill at an altitude of 983 feet MSL on a heading of about 296 degrees magnetic, and approximately three miles to the right of the southeast on-course signal of the Oakland radio range,
- Substantial power was being developed at the time of impact.
Final Report:

Crash of a Douglas DC-6B near Fort Collins: 50 killed

Date & Time: Jun 30, 1951 at 0200 LT
Type of aircraft:
Operator:
Registration:
N37543
Flight Phase:
Survivors:
No
Site:
Schedule:
San Francisco – Oakland – Salt Lake City – Denver – Chicago
MSN:
43144
YOM:
1950
Flight number:
UA610
Crew on board:
5
Crew fatalities:
Pax on board:
45
Pax fatalities:
Other fatalities:
Total fatalities:
50
Captain / Total flying hours:
10565
Captain / Total hours on type:
106.00
Copilot / Total flying hours:
5848
Copilot / Total hours on type:
1526
Aircraft flight hours:
3784
Circumstances:
Flight 610 of June 29, 1951, originated in San Francisco, California, and was scheduled to Chicago, Illinois, with en route stops, among which were Oakland, California, Salt Lake City, Utah, and Denver, Colorado. The crew consisted of Captain J R Appleby, First Officer H G Tower, Flight Engineer A T Petrovitch, and Stewardesses C J Baymond and F M Smith. The flight departed San Francisco on schedule at 1915 and after stopping at Oakland proceeded to Salt Lake City, arriving there at 2324. It departed Salt Lake City at 0011, June 30, 1951, 26 minutes behind schedule due to the reloading of bulky cargo At the time of departure the aircraft weighed 78,597 pounds, which was within the certificated gross take-off weight of 79,380 pounds, the load was properly distributed with respect to the center of gravity. There were five crew members, forty-four adult passengers and one infant on board. The approved flight clearance indicated an IFR flight, via Bed Airway 49, Green Airway 3, and Amber Airway 3, to Denver at a cruising altitude of 15,000 feet, with Omaha, Nebraska, designated as the alternate airport. The flight proceeded in a routine manner and at 0104 reported over Rock Springs, Wyoming, at 15,000 feet, estimating its arrival over Cheyeme, Wyoming, at 0147 and over Denver at 0207 2 Forty-three minutes later, at 0147, the flight reported having passed the Silver Crown fan marker (located 12 miles west of Cheyenne) and requested a lower altitude Accordingly, a new clearance was immediately issued-"ARTC clears United 610 to Dupont intersection, 3 descend to 8500 feet immediately after passing Cheyenne, maintain 8500 feet, no delay expected, contact approach control over Dacono "4 This clearance was acknowledged and the flight reported that it was over Cheyenne at 0147, at 15,000 feet and was now starting to descend. The Denver altimeter setting was then given the flight as being 30 19 inches. Nine minutes later, at 0156, the flight reported reaching its assigned altitude of 8,500 feet No further communication was received from the flight. At 0200, the Denver Control Tower requested the company radio operator to advise the flight to call approach control Repeated calls were made without an answer. It was later determined that Flight 610 had crashed on a mountain (Mt Crystal) 18 miles west-southwest of Fort Collins, Colorado. All 50 occupants were killed.
Probable cause:
The Board determines that the probable cause of this accident was that, after passing Cheyenne, the flight for reasons undetermined failed to follow the prescribed route to Denver and continued beyond the boundary of the airway on a course which resulted in the aircraft striking mountainous terrain.
Final Report:

Crash of a Douglas DC-6 in Dallas: 28 killed

Date & Time: Nov 29, 1949 at 0549 LT
Type of aircraft:
Operator:
Registration:
N90728
Survivors:
Yes
Schedule:
New York – Washington DC – Dallas – Mexico City
MSN:
42895
YOM:
1947
Flight number:
AA157
Crew on board:
5
Crew fatalities:
Pax on board:
41
Pax fatalities:
Other fatalities:
Total fatalities:
28
Aircraft flight hours:
5260
Circumstances:
Flight 157 originated at LaGuardia Field, New York, for Mexico City, Mexico, with stops scheduled at Washington, D C., and Dallas, Tex. Departure from LaGuardia was at 2147, November 28 Between LaGuardia and Washington the flight was reported to be uneventful with all of the aircraft's components functioning normally. At Washington, a flight plan was filed with, and approved by, Airway Route Traffic Control It specified Instrument Flight Rules to Dallas, with Wichita Falls, Tex, as the alternate, a cruising altitude of 18,000 feet, and a flight time of 5 hours and 4 minutes The gross height of the aircraft at takeoff was 82,298 pounds, which was 3,577 pounds less than the maximum allowable gross weight of 85,875 pounds, and the disposable load was distributed so that the center of gravity was within prescribed limits. At 0206 the flight requested and received permission to change its flight plan to Visual Flight Rules A posit-,on report was made over Nashville at 16,000 feet at 0254 and a descent was started to 6,000 feet When approaching Nashville, 1 No 1 engine had started backfiring at intervals of about 20 seconds Various corrective measures, including the application of alcohol and carburetor heat, and the richening of fuel mixture, were applied but were not successful and the backfiring continued. The captain and the flight engineer discussed the malfunctioning following which No 1 engine was feathered at a point about 25 miles southwest of Nashville at approximately 0300, however, the feathering was not reported to the company until 0429, where the flight was in the vicinity of Altheimer, Ark, a routine position reporting point about 125 miles beyond Memphis At that time, the crew advised a change of aircraft on arrival at Dallas. When 15 miles northeast of Dallas, at 0536, the flight was given permission to enter the traffic pattern at Love Field, Dallas, with a right-hand turn and instructed to land on Runway 36 The altimeter setting of 29 83 inches and the weather, which included unlimited ceiling, a visibility of 15 miles and a north-northeast wind of 5 mph, were given the flight The captain and the flight engineer conferred regarding returning No 1 engine to service and decided against doing so. The crew then went through the pre-landing cheek The landing lights were turned or and the Plans were lowered to the 20 degree position. The flight turned -flight to final approach when approximately over the Range Station which is 2 2 miles south of the approach end of Runway 36 At this time its altitude was estimated to be 1200 feet AFL 2 by the captain and 800 feet AFL by the first officer At a distance of about 1 1/2 miles from the approach end of the runway, the landing gear was extended. Shortly thereafter the flaps were extended fully, the turn to final placed be aircraft to the left of the runway Accordingly an "S" turn was made to correct the misalignment During this "S" turn the aircraft skidded to Its left, the air speed dropped abruptly and the aircraft settled rapidly. At this point the captain increased power to engines Nos. 2, 3 and 4 in an attempt to maintain control. Control tower operators watching the approach estimated that the aircraft cleared by 75 to 100 feet obstruction lights mounted on 30-foot poles on a power line located 800 feet south of the approach end of the runway. The aircraft continued in a generally northwest direction, across the airport on a heading about 40 degrees to the left of Runway 36, in a tail low attitude. Its air speed continued to fall, its attitude became increasingly nose-high. and a stall developed just prior to striking a hangar and other buildings on the northwest side of the airport. Both pilots and 26 passengers were killed.
Probable cause:
It was determined that the accident was caused by a faulty execution of an engine-out approach on part of the crew.
The following findings were noted:
- The captain failed to align the aircraft with the runway centerline after the final turn,
- After realizing the misalignment, the captain attempted to correct it with a risky "S"-turn at low altitude. There is little room for error if a problem arises during this maneuver because as the angle of the bank increases, so does the probability of stalling the airplane,
- The crew made no attempt to balance the airplane’s fuel load after the No. 1 engine failed. The DC-6 is equipped with four main fuel tanks that serve individual engines, while a network of valves allow fuel to be transferred from one engine’s tank to feed other engines. The crew did not cross feed fuel from the tank serving the failed engine to balance the plane's weight as recommended in the flight operations manual. Flight 157 had flown for almost three hours with the No. 1 engine out, and the CAB concluded that the No. 1 main fuel tank was holding about 1,400 lbs (635 kg) more gasoline than the other three main tanks when the plane arrived at Love Field. The investigators primarily attributed the left wing’s sharp drop to the excessive weight of the fuel at its outboard end,
- The captain applied excessive rudder during the “S”-turn, causing a condition known in aviation terminology as a skid. This maneuver would have caused the plane’s airspeed to drop, and according to the CAB findings, it caused the fuel in the No. 4 main tank to slosh away from the fuel outlet, lowering the engine’s fuel pressure,
- The captain’s application of full throttle to both right-hand engines caused to airplane to turn further to the left due to the relative lack of thrust from the single functioning left-hand engine. This exacerbated his loss of directional control,
- The first officer disobeyed the captain’s order to raise the wing flaps, and did not tell the captain,
- The first officer misinterpreted the No. 4 engine’s fuel pressure drop as a sign of incipient engine failure and feathered the prop. However, the CAB partially exonerated Lewis for this act, concluding that the craft was so close to the ground at that point that his mistake probably had little influence on the final outcome,
- Excessive elevator input by the captain caused the aircraft to stall.
The CAB concluded that the accident could have been avoided if the crew had held the plane straight and level when the misalignment was first noticed, then raised the flaps, climbed to a safe altitude, circled the airport, and attempted another landing. The CAB concluded that there were no factors present that would compel the crew to land immediately despite the sloppy approach, such as rapidly deteriorating weather or a shortage of fuel.
Final Report:

Crash of a Douglas DC-6 in Wake Island

Date & Time: Nov 15, 1948
Type of aircraft:
Operator:
Registration:
PI-C291
Survivors:
Yes
Schedule:
Manila - Wake Island
MSN:
43060/100
YOM:
1948
Crew on board:
0
Crew fatalities:
Pax on board:
0
Pax fatalities:
Other fatalities:
Total fatalities:
0
Circumstances:
After landing at Wake Island Airport, the four engine aircraft encountered difficulties to stop, overran and came to rest. There were no casualties but the aircraft was written off.

Crash of a Douglas DC-6 in Northwood: 32 killed

Date & Time: Jul 4, 1948 at 1503 LT
Type of aircraft:
Operator:
Registration:
SE-BDA
Survivors:
No
Schedule:
Stockholm – Amsterdam – Northolt
MSN:
43119
YOM:
1948
Region:
Crew on board:
7
Crew fatalities:
Pax on board:
25
Pax fatalities:
Other fatalities:
Total fatalities:
32
Circumstances:
The four engine aircraft christened 'Agnar Viking' was approaching RAF Northolt when the crew encountered low visibility due to poor weather conditions. After being cleared by ATC to descent to 2,500 feet, the crew was unable to locate the airport and decided to return to Amsterdam-Schiphol Airport. Few minutes later, while climbing to an altitude of 3,000 feet, the aircraft collided with a Royal Air Force Avro 685 York C.1 registered MW248. This second aircraft was completing a flight from Malta-Luqa with four passengers and a crew of three. Following the collision, both aircraft went out of control, dove into the ground and crashed in a wooded area located in Northwood, about 4 miles north of RAF Northolt. Both aircraft were destroyed and all 39 people were killed.
Probable cause:
The cause of the loss must in all probability be found in the field of human fallibility on the part of those responsible for the control of the aircraft from the ground or the flight of the aircraft in the air. Investigators found that the separation of 500 feet in force in the Northolt area, provided an inadequate margin of safety and recommended that it should be increased to 1,000 feet for the Metropolitan Control Zone. The report also discussed the standard setting for altimeters (known as QFF) that had been introduced in May 1948 for aircraft above 1,500 feet within control zones, and that any error in setting the barometric pressure of one millibar gave an error of 28 feet.