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oug ferried the Hars Convair out from South Africa last year.
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I saw a media photo last year of that HARS Convair taken during its initial take off climb. As a former Convair 440 pilot from over 50 years ago, I noticed that one upper cowl flap was fully open on one engine. The angle of the photo restricted the view of both upper cowl flaps. Normally that would be a serious event as the drag from a fully open upper cowl flap would be prohibitive in event of an engine failure at that stage.
My thought was maybe the cowl flap motor was inoperative and the crew had perhaps mechanically wound the cowl flap to the full open position for a ferry flight due lack of spares at the point of departure. That would be inconceivable to me as the CHT on that engine would be very low with all that cooling airflow through the engine and effect on the cylinders. I wrote to HARS for their comment but received no acknowledgement
Please forgive the longish high-lighting of a previous post. Photos accompanying the official report prove beyond doubt the accident aircraft departed with the top and bottom cowl flaps fully open. See above previous highlighted comment. The photo shows a fire that can be seen through the open top cowl flap. Is it possible that the intensity of the fire could be made worse by the airflow through the open cowl flap?
The drag would be significant. I was a QFI on the RAAF Convair 440 Metropolitan based at Canberra in the 1960's era. As far as I recall it was unheard of to take off with the cowl flaps fully open.
Again if my memory serves me correctly, for take off we selected the cowl flaps selector switches to a position called "Trail" or similar name and the cowl flaps would then close to a position about two inches open. This gave minimum drag commensurate with keeping the CHT within take off limits.
The report states the propeller of the engine on fire was not feathered; indeed the fire drill was not actioned either. At impact, evidence indicated the engine was delivering very little power. It is no wonder the aircraft was unable to maintain height on one engine given the high density altitude, the drag from a windmilling propeller and the fully open cowl flaps on the engine. It is difficult to know why the company policy required the cowl flaps to be set fully open for take off. It was the same cowl flap policy apparently that HARS used for the first Convair ferried to Australia.
The single manifold pressure gauge with twin needles marked 1 and 2 and the single RPM gauge with its twin needles marked 1 and 2 which were on the Convair 340 and 440, could be a bit of a trap for the unwary. I experienced a runaway left propeller at 500 feet after take off at Canberra in a Convair 440. The very first indication was the very loud increase in noise from the left side of the aircraft. A quick glance at the RPM gauge showed a rapid "split" occurring between the number one and number two needles and for a few seconds it was difficult to confirm if one needle was indeed reducing in RPM and the other increasing in RPM. I would imagine the same would apply to a manifold pressure gauge with its dual needles. The South African report reveals there was initial uncertainty among crew members which engine was the problem. With the single manifold pressure and single RPM gauge design, I can understand that.
The report stated the LAME was handling the engine controls. That is another trap IMHO. Too many cooks spoiling the broth, as the saying goes. I saw this happen once. During my time as QFI at Canberra on the Convair 440, I was tasked to test the pilot of a USAF Convair 340 for his instrument rating. The Convair 340 (or maybe it was a Convair 240 I am unsure now) was based at Canberra for the use of the United States Consul General and his staff. The pilot was a Major in the USAF and it was policy to carry a "Crew Chief" who had the rank of Staff Sergeant I think. In other words he was an LAME who was primarily responsible for the servicing of the US Embassy aircraft. The crew chief sat in the jump seat and among other duties he started the engines (which could be a quite complicated procedure involving multi-fingered switch flicking and lever operation). He also handled the throttles, pitch and mixture levers, and cowl flaps - even though a co-pilot might be present.
During the instrument rating test, one engine was shut down in cruise and checklists followed. Except I noticed the mixture on the live engine was still in lean even though the live engine was at METO power. The crew chief who was doing the engine handling did not notice the lean mixture. The captain missed it as well. He was relying 100 percent on the crew chief to push and pull the appropriate levers and knobs. When I pointed out to the captain the mixture on the live engine was not placed in rich he got very cranky and harsh words were exchanged between the hapless crew chief and the captain. The captain refused to accept he was equally to blame for the missing checklist item.
Afterwards I pondered this situation and came to the conclusion there were too many hands on the flight deck sharing simple tasks and if there were already two pilots in a two crew aircraft it was superfluous to have someone else, no matter how qualified, reaching between them operating engine controls.