A Dangerous Blend, Mixing Avgas with JP-1

When you mix Avgas (aviation gasoline) with Avtur (Aviation Turbine Fuel) and refuel a Douglas DC-4 with it, it has tragic consequences as you will learn in this story.

The DC-4 took off from Francistown runway 11 at 02:32. The engine temperatures started to rise, even after opening the gills. When temperatures exceeded the limit, the engines started backfiring. A left hand circuit was made to return to the airport, but the aircraft kept descending and crash-landed 3600m short of the runway. The aircraft struck some trees and burst into flames.

Power loss on all 4 engines due to fuel contamination. A load of Jet A1 (Avtur) fuel had been unloaded in one of the Aviation gasoline (Avgas) tanks, causing a contamination of 25-30%.

THE BEGINNING

Wenela Air Service got its name from the Witwatersrand Native Labour Association, which provided laborers for the South African mining industry. They were formed in 1952 with Africair as the operating company using DC-3’s. By 1960 the fleet had grown to 12 DC-3’s and 2 DC-4’s and 100,000 miners were carried annually. The seven main routes connected Francistown to Mohembo (occasionally via Main), Mongu (via Livingstone), Lilongwe, Blantyre, Fort Hill (via Ndola end route to Fort Hill and via Lilongwe en route to Francistown) and Katima-Mulilu.

AFRICAIR LTD.

In 1946 Anglo Vaal Air Services named A.V. Air Transport and “Africair Servicing” amalgamated to form Africair Ltd. Both Companies were part of General Mining Industries.

In April 1951 Africair successfully operated a trial run for Wenela between Lusaka and Lilongwe to prove the viability of Gemmil’s plan. As a result of this successful flight Wenela Air Services was formed in 1952 with Africair as the operating Company using Dakota aircraft with Francistown as their base. Later the DC-4 was introduced.

Miners were carried for free to Francistown and then transported via road and rail to the mines. Wenela was based and maintained its aircraft at Francistown and for a time in Bulawayo where Africair had a maintenance base, (then Rhodesia, now Zimbabwe).

THE CRASH

On the morning of the 4th April A2-ZER was scheduled to fly a passenger load of repatriating Malawian mine workers back to Malawi.

At 0232 hours after a normal engine start and run up A2-ZER took off from runway 11 Francistown for the flight to Malawi. It appeared to pass the control tower at a lower altitude than normal and shortly after the pilot complained that the aircraft felt heavy and climbing was difficult.

Almost immediately after take-off and after retraction of wheels and flaps the temperature on all four engines started to rise and continued to rise in spite of opening the gills. As temperatures rose “off the clock” back-firing started, with fluctuating r.p.m.’s and loss of power and the throttles had to be held open to prevent them from hitting back. Back-firing, torching and increasing loss of power continued throughout the remaining duration of flight.

Contact was made between the control tower and the aircraft shortly after take-off and Capt. Strike who was operating the radio said “We are coming back”. The control Officer on duty in the control tower said “What’s the trouble, Bill” and Capt. Strike replied” Everything, and we are going down”. No further calls were received from the aircraft.

The aircraft made a left hand circuit with the object of returning to the airfield. At no stage did it reach a height of over 400 to 600 ft: and with rapidly increasing loss of power height could not be maintained. The aircraft completed almost three legs of the landing circuit but before being able to turn in onto runway 11 it crashed about two miles short of the threshold of the runway at approximately 0238 hours. Immediately before crashing the First Officer switched on the landing lights and all evidence indicates that the aircraft was in the correct attitude for a crash landing. The total time taken from take-off until the crash was 5.5 to 6 minutes.

The terrain where the aircraft came down was bush country with mainly bush and small vegetation. However three or four larger trees in a direct line with the path taken by the aircraft in crash landing contributed largely to the massive damage done to the body of the aircraft and to the break-off of a section of the tail which incidentally also enabled the six surviving passengers to escape out of the rear of the aircraft.

The fuel tanks were ruptured during impact and the aircraft caught fire immediately. It seems almost certain that in the absence of fire the number of survivors would have been considerably increased.

Captain Jimmy Miles, the Station Commander and Chief Pilot of Wenela Air Services, remembers April 4th, 1974 well. He was woken up by his wife Rhona saying that an aircraft was ‘making funny noises'”. Instantly Jimmy was fully awake too. He realised in those fateful seconds that something was terribly wrong with their aircraft A2-ZER on its flight to Blantyre, Malawi. He remembers vividly running to the window and seeing the plane’s engines flashing as it went passed. He phoned the control tower and asked what was wrong with the aircraft.

“Clarrie Clarence”, the controller, replied: “Bill Strike says that everything has gone wrong…. he says he’s coming in to land. It’s turning on final now…Oh Christ, it’s crashed!”

Capt. Miles asked his wife to go to the homes of crew to give as much comfort as she could to the wives. He did not think anyone would be coming out of the crash alive.

Rushing to the airport he took a Land Rover from the hangar and together with D.P. Smith rode along the Orapa road stopping as close as possible to the crash site, then running the remaining distance through the bush. He described the scene as a giant funeral pyre, a mass of flames reaching up to the clouds which were 250 to 300 feet high.

De Villiers the duty engineer took another route along the extension of runway 29 arriving there first. He took his friend Red Redlinghuis to the hospital, the six surviving passengers followed after being loaded on trucks that arrived shortly afterwards.

The first thing Capt. Miles did after leaving the scene of the accident, was to obtain a police guard, and telex Blantyre where a plane had arrived earlier and ordered it grounded. Just as well, they were having difficulty starting the engines when the telex arrived, and the engines were later discovered seriously damaged. They only arrived there safely because the amount of contaminated fuel loaded at Francistown was not as much as the crashed aircraft, and so fortunately a second tragedy was averted. Distance from Francistown Airport to Blantyre-Chileka Airport as the crow flies is 995 km (622 miles).

The crash claimed the lives of 74 Malawian Miners as well as the pilots, Captain William “Bill” Strike, 54, and First Officer John Ernest “Butch” Nightingale, 42, and an air conductor named Gabriel Khute. Flight Engineer H.J. Redelinghuys, Air conductor Vincent Randingwana, and five passengers survived the crash.

Redelinghuys, 51, who had an incredible escape apparently had been catapulted by the impact through a window opening of the plane from his jump seat behind the pilots.

Vincent Randingwana who was on his second flight felt routine enough for him to be catnapping as the plane took off. Within a few minutes he was woken up by worried shouts by the miners.

He found himself lying on the ground in a circle of flame. He could see trees through the flames and got up and ran through the flames to safety burning himself badly. On hearing screams nearby he ran back through clear patches in the flames and pulled three men to safety.

The shock of the tragedy came home to a stunned Francistown, with its close knit community. The Town rallied, from Dr. Moeti, superintendent of the hospital and his staff, the wives, colleagues, in fact everyone.

Capt. Miles and his wife Rhona attended a moving service for the Conductor in the African Church at Francistown. I have never heard such singing – it went on and on, as only Africans can. One hymn after the other, as you can imagine we were all under stress, not only having lost some good friends, but, also trying to comfort families, answering questions etc. On leaving the church in tears I was asked to make a speech at the grave site. This is what I said: “Together we have flown to the North and back, Shakawe and back. We have flown in the sunlight and the dark. We have flown through rain and hail, storms and weather. Seen the sunrise and you have flown into the sunset and deep of night. I am proud to have had you with me. Rest in peace.”

The crew were buried in a moving service at the Francistown cemetery, and because of the problem of identification, the plans to fly the passengers bodies home were scrapped. They were given a mass funeral at the Botswana border township’s cemetery.

It also brought to a flaming end the safety record of Wenela Air Services through no fault of the operator. In the 22 years of its operation it had never had a fatal accident.

THE ACCIDENT BOARD

The Board found that no blame could be attached to the crew in respect of the cause of the crash, and in the circumstances prevailing the crew did all that could be expected of them to minimise the effects of the crash.

That fuel contamination occurred in the aircraft because it was refuelled on the 3rd April, 1974 from refueller AV 810 with over 4000 litres of Avgas contaminated with Avtur. The degree of contamination in the aircraft was between 25-30%.

The Board was satisfied that the accident was due to the act default or negligence of Shell and B.P. Marketing Services (Pty) Ltd, or of persons in its employment and it remains for the Board to decide whether and to what extent to award costs against Shell and B.P. Marketing Services (Pty Ltd).

THE END

By the late 60s and early 70s Southern Africa was placed in a dilemma when political refugees from South Africa were granted asylum by the Botswana Govt. and were transported out of Francistown Airport . On one occasion an East African Airways Dakota VP-KJT which had been chartered to carry refugees to Tanganyika, was mysteriously burnt out while on the ground at Francistown.

This spurred the demands by the African States to the North against South Africa and did nothing to help Wenela Air Service which already was on a political tight rope.

Air Malawi also wanted a slice of the pie and after applying political pressure also began operating and transport miners into Francistown in 1973.

They were using modern Turbo Prop HS748 aircraft against the fairly obsolete aircraft of W.A.S. Furthermore the DC-4’s were fitted with low back steel seats whereas the HS748s were using normal passenger seats. This had an adverse effect on the recruits. Never the less the DC-4s continued to operate to the end.

After the tragic DC4 crash on the 4th April 1974 through no fault of W.A.S. Dr. Hastings Banda, the President of Malawi, banned W.A.S. from flying Malawian miners.

The Chamber of Mines then approached Safair to use their Lockheed Hercules aircraft to transport the Malawian miners in conjunction with Air Malawi direct to Jan Smuts airport.

Wenelas flying operation was brought to an end on June 30th 1977. The last six months of its operation only 895 miners were flown by W.A.S. The continent’s busiest Airline had now only a fleet of three Dakotas.

So ended an era. A tragic crash coupled with politics was the beginning of the end for what was then the busiest flying operation in Africa.

History of Douglas DC-4 A2-ZER c/n 27242

Bought by Douglas Aircraft Company 13 December, 1945 and converted to DC-4, conversion No. 24. Bought by Delta Airlines 2April, 1946 registered as N37475. Bought by Pacific Northern Airlines 27 February, 1953. Bought by Overseas National Airways in 1957, registered as N410NA, named “Loma D”. Sold to Witwatersrand Native Labour Association of Rhodesia (WENELA) and registered ZS-CLN in 1960. Reregistered VP-YST March 1961, reregistered September 1968 as A2-ZER.

Sources: Ken Fuller, The Kjell Oskar Granlund Collection, Flyvertosset, SAA Museum Society, Perry-Castañeda Library, Flyvertosset