At this time of year, pilots are wondering about winter oil and what is the best practice for their airplanes.
Many pilots are still confused about when, where — or even if — they should use a multigrade oil. They also wonder whether they can go back and forth without harming their engines. [Read more…]
In my past two columns I put forward the idea that for the future of general aviation, we need to update technology to meet the demands of a changing world. I would like to further that discussion and answer a few of the comments from readers.
The first step is to forget the 100 unleaded avgas program and go to a two fuel system. The two fuels would be very similar, with one being the present 100LL and the other being the same fuel only without the lead. It would have an octane of around 94 lean rating (call it 94UL) and would meet all of the other properties of 100LL.
Now I know there is the problem of FBOs needing two fuel systems. But many of them presently have two systems or sell mogas.
The advantages of the two fuels are very significant. [Read more…]
In my last column “Standing still too long,” I wrote about the problem with general aviation not moving ahead technically. This resulted in a significant amount of feedback from readers.
The comments mostly centered around GA being too small a business to pay for new technologies, all GA aircraft are hand built, the fact that the FAA would never approve new technology, and the always present, “who will pay for it?”
This month I thought I would try to come up with a solution to all of these problems. [Read more…]
In my June column “Concern for the bottom line hurts general aviation,” I talked about the bottom line concerns of GA manufacturers. I received a significant amount of feedback, both positive and negative. I appreciate both types of feedback and I would like to address one of the comments.
Gbigs wrote: “There was never a time when the bottom line was not first order for a real business. Sure companies blow money on R&D if they can afford it, but make no mistake — there is no R&D without a bottom line.” [Read more…]
I recently received a nice note from John Machamer about his 1930 Kinner B-5 engine. The factory recommends an oil operating temperature of 122°F to 158°F during cruise conditions.
But John had a problem because his oil temperature ran at only 120°F.
Even after closing off one air inlet he could only get it up to 130°. While this is in the recommended range, it’s still very low. John is concerned he may not be getting proper lubrication in the rear gear cases, and was wondering if a multi-grade or single grade would be better for his engine. [Read more…]
A few months ago I spent an evening with some friends I had not seen for a while. After a few bottles of a fine Merlot, we discussed most of the world’s most pressing problems.
The conversation covered many points, including the accident in a commercial jet liner when an engine exploded and a piece of the engine hit the fuselage, killing a passenger in a window seat.
My take on the accident was of course sadness for the loss of the passenger, but also great admiration and respect for the pilot who controlled the aircraft and saved all of the other passengers and crew. A true hero.
The other people in the conversation were all trained professional people, but their take on the incident was that the accident was entirely the fault of the airline. And that the airline and aircraft manufacturer were liable for the accident and will need to pay her family a lot of money.
Their reasoning was that the only cause for failure would be lack of or improper maintenance. [Read more…]
When I got out of college in 1967 and started work, most companies were run by technical people who supported research and development.
In the lab we were allowed a lot of latitude to work on related projects that may not have an immediate payout.
This lasted for a few years, but with the change in economy, many companies started to shift more and more to the “Business School” model. If it had settled to a happy medium that would be good, but that did not happen. The business-types took over more and more companies. This resulted in the near failure of several car companies and others.
Some companies have shifted back, but the general rule in the business world today is that the bottom line is the only concern. This has hit the general aviation world in many ways. [Read more…]
Lately, I have received numerous questions about grease. The general theme of most of them is “why can’t I use synthetic grease from the local parts store in my aircraft?”
Synthetic lubricants are one of the present “now” or “buzz” words. If a lubricant is synthetic, people believe it will last forever and lubricate anything.
Synthetic-based oils do offer some advantages, especially in extreme high or low temperatures. But they are not the end-all, cure-all that people are hoping for. [Read more…]
In a previous column, CYA, the FAA and the new unleaded avgas, I discussed the problems the FAA may have with the new proposed unleaded 100 octane avgas.
In addition to the lower octane characteristics of the avgas, one of the big concerns is exhaust valve recession.
I received a number of responses to the column, both positive and negative. The best email was from Larry Wheelock, who commented about the example of possible valve recession in Franklin engines.
He noted that the low performance Franklin engines were qualified on unleaded gasoline and, because of their low operating temperatures, actually had problems running on higher lead content fuels. The valve face temperatures ran at a temperature too low to scuff off the lead byproducts of combustion.
I apologize to Franklin owners; I should have been more specific as to which models could be affected.
This brings up the question as to which engines may be affected by valve recession with the unleaded fuel. [Read more…]
At what temperature does piston aircraft engine oil break down?
This is not the same as the maximum oil sump temperature allowed for your engine. Both Lycoming and Continental recommend a maximum oil temperature of around 245°F.
Running at 245° may be OK during break-in or during climb out, but I do not recommend running continuously at cruise condition at this temperature after your engine is broken-in.
In many aircraft, the only indication of how your engine is operating is the oil temperature. A 245° oil sump temperature is an indication of incorrect tuning or engine installation. [Read more…]
