Mark:
**I understand some have reservations about running the fuel pumps for extended periods and I can understand that. **
The boost pumps are designed to run for extended periods without difficulty. It should not be a problem in any way.
**However, everything in the owner's manual must be approved or at the very least accepted by the FAA. **
That is a commonly held belief, but is misplaced. The FAA only has anything to say about items that are listed in the LIMITATIONS section. Other items are not passed on by the FAA.
**Obviously, heat has something to do with the problem and altitude would only aggravate the heat issue.**
The issue is the vapor pressure of the fuel. It generally runs in the 7 psi range but can vary a bit. This is altered by heat and greatly affected by altitude Ambient pressure). By 18k feet, the ambient pressure is 7.3 PSI. Using the boost pump can raise the vapor pressure altitude. The hotter the fuel, the lower the vapor pressure altitude.
**I was interested to see that someone had taken the time and effort to do the research to cool the engine driven fuel pump. (I am wondering if the affected aircraft had intercoolers).**
"A man without data is just another person with an unsupported opinon." If I have an unsupported opinion, I will not offer it without saying that it is unsupported by any data. As for the intercoolers, they have NO effect on this issue in any way.
I visit seven forums each day, answering questions about the specifics of engine management. I have never been exposed to the vitriolic attacks anywhere like what goes on here. That says something about a group which allows that sort of behavior. Every other forum I visit has rules of behavior which restrict personal attacks. Heated debate is welcomed and in many cases quite healthy, but personal attacks are not. Besides, the DATA is the expert. If you have no data to offer to support your opinion, it is just another unsupported opinion and that is all there is to it. I visited here because one of your members asked me to participate in an effort to correct a lot of the unsupported opinions which were being shoved down your throats by forum bullies. Much of those strong opinions are not supported by the science or the data but are shoved down your throats by your forum bullies anyway. It appears that this forum's moderators are unable/unwilling to enforce even a moderate level of civility. I don't have the time nor the inclination for that childish behavior as there are other places where the science and the data are appreciated and anyone acting as a forum bully is immediately excluded. I addition, the better forums require that people use their real names. It's a simple act that is polite. We all like to know who we are talking to. In my opinion, that is another reason this forum gets out of line and people are rude. It has been my observation that the only reason people are rude, is that they can get away with it.
If this forum were to adhere to a few simple rules of being polite and began using their real names, then I might be inclined to participate. Skymasters are really cool airplanes and there are a number of really neat people who own and fly them. 'Tis a shame that the group has allowed a few forum bullies to ruin it and shove information that is incompatible with the known science down its throat.
Good luck and if that were to change, somebody let me know and I'll consider returning for the SOLE purpose of offering educated and data-backed information on engine management.
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Walter Atkinson
Advanced Pilot Seminars
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