I would like to say thanks to you and King Air magazine for your help in asking Tom Clements my question about Cleveland brakes. I must say I was surprised to have emailed you the question on Friday afternoon and getting a response that night from Tom. I was in the middle of a three- and four-phase check and had hoped to get an answer soon enough to take advantage of a better brake.
Thanks to all, I have ordered the new brakes for my B200. I am sure I will be pleased with the new brakes.
A Recent Flight with Executive Air
I am Managing Director, as well as one of the pilots of Executive Air, a charter and MEDEVAC company of 30 years, based at Charles Prince Airport in Harare, Zimbabwe.
Caroline, my partner in business as well as life, and I were returning to Harare after picking up our patients from Ghanzi, in western central Botswana. We were flying our King Air 200 on this MEDEVAC and had been cleared direct to Harare from Ghanzi at FL270. It was a dark, stormy night with some lightning from the dissipating storms that we had negotiated on the way in to Ghanzi.
As we were reaching our flight level, we heard South African Airways SA203 talking to Gaborone Control about their MAYDAY call. They had smoke in the cockpit! This got our attention and our thoughts were with the crew and passengers on that aircraft. We heard them downgrade the MAYDAY to a PAN call and they told Gaborone that they would be going back to Johannesburg. I think they had 215 passengers and 12 crewmembers on the aircraft. Gaborone told them that they would be watching their progress constantly. The crew, a man and woman, sounded very much in control, although the situation was still tense! They then requested permission to jettison fuel along the airway they were flying. I thought to myself that this was so that they would be within the weight limit the aircraft had for the landing when they got back to Johannesburg. Gaborone told them that they would need to wait for eight minutes before dumping, in order to have the required clearance between another aircraft apparently on the same routing. Gaborone duly called them at the appropriate time and told them to go ahead with the fuel jettison. Caroline and I chatted about the possible situation that these chaps were in and we both agreed that we were glad it wasn’t us in that plane, wherever they were.
We were making good speed at FL270, about 260 knots despite the clouds and lightning. We were passing south abeam Maun at about 1940Z time when there was a bright lightning flash and the plane shuddered a bit. Caroline and I mentioned that we may get a bit of turbulence from the weather. I put on the seat belt sign with chimes to remind our passengers to tighten their belts.
Then Caroline said she was losing an engine! We both checked and confirmed the left engine torque had started fluctuating. Then the engine started surging with loud bangs and flames blowing from the exhausts to beyond the wing. This was shortly followed by the same on the right engine!
Adrenaline was now at peak! We checked all the gauges and besides fluctuation on the torque meters, the other gauges were holding steady with the correct readings! However, the surging and noise were seriously off-putting and we were concerned for our safety, to put it mildly. We had not covered anything like this before in our sessions in the simulator or in our previous flights.
When the situation had not gotten any better for what was probably only a couple of minutes, we decided to divert to Maun. I informed Gaborone control that our engines were surging and that we wanted to divert to Maun to assess the problem. Caroline turned left toward Maun and started the descent. As she did that, we got the engine fire warning in cabin on our annunciator panel. The engines were still surging and spitting impressive flames; however all appeared to be coming out of the exhausts and nothing from the nacelles. I cancelled the warning light and kept a watch on the engines. At the same time, I was talking to Maun and telling them we were descending for their field with engine problems.
During the descent, I thought about the SA203 fuel jettisoning and told Caroline that is what I thought was the problem. I told her to stop the descent and climb back to FL250 and turn back on course for Harare. We would see if the problem would go away. It was not long after returning to our course that the two engines started performing properly again. I told Maun and Gaborone that we had resumed our course and that all appeared okay!
I then called SA203 and asked them if they had jettisoned their fuel in the vicinity of Maun? Yes they had! I thanked them for the excitement and all returned to normal for the rest of our flight home.
What had happened? I believe that we had been overlooked by Gaborone control and had been allowed to fly through the mist of jettisoned fuel from SA203! When we entered this fuel rich air, the engines were choked with too much fuel and not enough air for combustion. Then, maybe there were less dense patches and the engines then flamed up with the excess fuel lighting up outside the engines. This went on for a couple of minutes, although it felt much longer!
The engines then performed flawlessly for the rest of the flight. We are now waiting for the report from our engineers to see if any damage has been suffered within the engines. We’ve got crossed fingers!
Has anyone else had a similar experience or have any brainwaves on alternative courses of action in this situation?
Thank goodness, Executive Air is still here to fly
General Manager, Executive Air
Editor’s Note: As a follow-up to his letter, Mr. Mordt sent the following:
We were advised by the Pratt and Whitney representative for Africa to do the following, which he received from headquarters.
If there were no exceedances of engine parameters, it was recommended to do a boroscope of the hot section, compressor, including access via the bleed valve in order to see that there was no ignition in the compressor. As a precaution, an oil change should be carried out as a possibility that fuel entered the oil system. If you need any assistance regarding BVI findings, please forward the pictures or video for further evaluation. If possible please provide airframe and engine details (airframe and engines serial numbers) including hours and cycles for our internal system requirement.
My engineers have had a good look at the engines and did the boroscope as recommended. We have also taken an oil sample from the engines and sent them for analysis. The engines have no symptoms or signs of any damage from the incident. We have since done another MEDEVAC flight and the aircraft performed flawlessly.