pblake
Member
It seemed to me that the fuel tank service bulletin issued by Van's was precipitous, and not well thought through. In many ways, the cure seemed worse than the disease, for example, working on and opening an empty fuel tank filled with gasoline fumes, or leaving remnants of proseal in the tank from removing a prosealed flop-tube. Here's the letter I sent to Van about it:
Dear Van,
I was very surprised and disappointed on seeing your Mandatory Service Bulletin requiring fuel tank changes. In my case, I have capacitive probes for fuel quantity measurement, and no inspection plate to remove. Even if I did have plates, there?s less than a 2? gap between the wing skins and fuselage of my RV6. I won?t whine about tearing up very expensive paint, or removing the wings to get at the tank, or even that this may cause an insurance problem if I fail to do it. Instead, I question your logic and your process of issuing this bulletin.
I?m wondering why you didn?t at least have a comment period so you could gather input from the fleet, before issuing this bulletin. The FAA finds public comment useful; I?m surprised you don?t as well.
I have heard of two incidents involving ?alleged? (your term) fuel pick-up tube problems. In one, there was plenty of warning that something was amiss, yet the plane was flown anyway (rather than ground tested), without determining and rectifying root cause. Even then, it seems that simply switching tanks would have prevented the accident. In the second instance, switching tanks would have prevented the accident as well. How many times have we heard of fuel starvation accidents where the pilot failed to switch tanks, even though plenty of fuel was available in the other? It seems to me that pilot error was a major contributing factor in these accidents. Perhaps an article on the importance of proper emergency procedures for engine-out emergencies would have been appropriate, since that would address prevention of such fuel starvation accidents.
Given a fleet of approximately 4500 aircraft, 2 incidents (both of which could have been prevented by appropriate pilot action) represents an accident rate of 0.044 %. This level of risk doesn?t seem sufficient to warrant the draconian nature of your service bulletin ? especially unilaterally, without comment.
Further, it seems to me that a vanishingly small probability exists that one tank would be dry while the fuel pick-up tube malfunctioned in the other, or that both tubes malfunctioned at the same time. These seem to me to be the only conditions under which an engine stoppage due to fuel pick-up tube malfunction could not be rectified by appropriate pilot action e.g., switching tanks.
Many will say that you did this to protect yourself from liability ? a completely understandable motive. It seems to me however, that mandating the opening of 9000 fuel tanks by amateurs, drilling of holes in sensitive areas, resealing etc. (and in the case of those of us with capacitance senders and no removable end plate, creating and sealing a large hole), not to mention the obvious danger of fire when working around aviation gasoline and fumes, is a case of the cure being worse than the disease. It seems to me that you expose your company to much more liability in the case of accidents that will be construed as directly or indirectly caused by or related to these ?repairs.?
It seems to me that a more rational approach would be to mandate a bore scope inspection of the fuel pick-up tubes, which could be accomplished with minimum fuss through the fuel drain plug hole. This would identify any problems, go a long way toward protecting you from fuel pick-up tube liability, and avoid entirely the liability of causing 9000 fuel tanks to be drained (and not flushed with water), opened, modified and reclosed.
I encourage you to consider all the ramifications of your actions, first and foremost with regard to safety. Secondly, with regard to the thousands of hours (and dollars) required for fleet compliance, and thirdly, with regard to your reputation for pragmatism, concern for costs, and generally doing the right thing.
Please rescind this bulletin, and issue another, more appropriate to the actual risk-benefit relationships in this issue.
Sincerely,
Peter Blake
Technical Councilor
RV6
Dear Van,
I was very surprised and disappointed on seeing your Mandatory Service Bulletin requiring fuel tank changes. In my case, I have capacitive probes for fuel quantity measurement, and no inspection plate to remove. Even if I did have plates, there?s less than a 2? gap between the wing skins and fuselage of my RV6. I won?t whine about tearing up very expensive paint, or removing the wings to get at the tank, or even that this may cause an insurance problem if I fail to do it. Instead, I question your logic and your process of issuing this bulletin.
I?m wondering why you didn?t at least have a comment period so you could gather input from the fleet, before issuing this bulletin. The FAA finds public comment useful; I?m surprised you don?t as well.
I have heard of two incidents involving ?alleged? (your term) fuel pick-up tube problems. In one, there was plenty of warning that something was amiss, yet the plane was flown anyway (rather than ground tested), without determining and rectifying root cause. Even then, it seems that simply switching tanks would have prevented the accident. In the second instance, switching tanks would have prevented the accident as well. How many times have we heard of fuel starvation accidents where the pilot failed to switch tanks, even though plenty of fuel was available in the other? It seems to me that pilot error was a major contributing factor in these accidents. Perhaps an article on the importance of proper emergency procedures for engine-out emergencies would have been appropriate, since that would address prevention of such fuel starvation accidents.
Given a fleet of approximately 4500 aircraft, 2 incidents (both of which could have been prevented by appropriate pilot action) represents an accident rate of 0.044 %. This level of risk doesn?t seem sufficient to warrant the draconian nature of your service bulletin ? especially unilaterally, without comment.
Further, it seems to me that a vanishingly small probability exists that one tank would be dry while the fuel pick-up tube malfunctioned in the other, or that both tubes malfunctioned at the same time. These seem to me to be the only conditions under which an engine stoppage due to fuel pick-up tube malfunction could not be rectified by appropriate pilot action e.g., switching tanks.
Many will say that you did this to protect yourself from liability ? a completely understandable motive. It seems to me however, that mandating the opening of 9000 fuel tanks by amateurs, drilling of holes in sensitive areas, resealing etc. (and in the case of those of us with capacitance senders and no removable end plate, creating and sealing a large hole), not to mention the obvious danger of fire when working around aviation gasoline and fumes, is a case of the cure being worse than the disease. It seems to me that you expose your company to much more liability in the case of accidents that will be construed as directly or indirectly caused by or related to these ?repairs.?
It seems to me that a more rational approach would be to mandate a bore scope inspection of the fuel pick-up tubes, which could be accomplished with minimum fuss through the fuel drain plug hole. This would identify any problems, go a long way toward protecting you from fuel pick-up tube liability, and avoid entirely the liability of causing 9000 fuel tanks to be drained (and not flushed with water), opened, modified and reclosed.
I encourage you to consider all the ramifications of your actions, first and foremost with regard to safety. Secondly, with regard to the thousands of hours (and dollars) required for fleet compliance, and thirdly, with regard to your reputation for pragmatism, concern for costs, and generally doing the right thing.
Please rescind this bulletin, and issue another, more appropriate to the actual risk-benefit relationships in this issue.
Sincerely,
Peter Blake
Technical Councilor
RV6
