Jump to content


  • Content Count

  • Joined

  • Last visited

About GlennM

  • Rank
    Senior Crew Member

Profile Information

  • Location
    Orlando, Florida
  • Gender

Recent Profile Visitors

The recent visitors block is disabled and is not being shown to other users.

  1. It...is...alive!... No worries. New information, opinions, or news is always good
  2. I would guess fatigue. Side to side loading looks wrong for a bad landing. Overload typically goes through the weld throat (middle) of the weld.
  3. Why would only one CHT be affected and jump around if it were the radiator? TCs don't bounce. It is probably a connection problem. My CHTs "bounce" when I need to clean my grounds for the Dynon.
  4. GlennM

    Piston Head

    My point is that there are defects allowed in most engines and just detecting one does not mean you need to do something about it. If you see a hot spot discoloration on a valve during a borescope, do you replace the valve immediately? If you see a flake of metal in your oil filter, do you do an immediate teardown and overhaul? I think not. In the case of exhaust valves, would the limit of acceptable damage be detected with a compression check? Just because something is old does not mean that it is no longer good. I am sure at least some of those in-flight exhaust valve failures had low compression checks. It is only recently that camera and lighting technology have reached a point where borescopes are cheap to purchase. This will greatly aid the adoption by mechanics.
  5. My dad was a mechanic for Pratt and my grandfather was a sheet metal mechanic for Pratt, so I understand listening to the guys actually doing the work.
  6. I worked for Pratt and Whitney testing primarily military engines like the F100, F119, and F135. Now, I work for Siemens Energy testing gas turbines for power generation.
  7. GlennM

    Piston Head

    What do you save by detecting the exhaust valve heat damage earlier than a differential compression test?
  8. Sounds like you need to replace the potentiometer on the flap actuator and recalibrate the flaps.
  9. In my experience, most metals burn given the right atmosphere. Titanium is self-oxidizing like magnesium. So you have to take the heat away or interrupt the chemical reaction somehow. Roger should know, he was a fireman. I watched Backdraft twice, so I am an expert, too.
  10. Congratulations! I am sure you will enjoy it. It is much lighter than a Cirrus! The CTSWs are really sporty and I prefer their handling.
  11. Yes. Mine, also, lists the site as not secure. Maybe a certificate issue.
  12. There is nothing wrong with following the current Rotax maintance manual for life limitations and maintenance periods. Replacing earlier than their limit is opening yourself up to maintenance-induced failure, as you mention. But, people do this for other reasons like expediency; "while they are at it", or costs. It is probably cheaper to replace the spark plug than inspect and clean it if you are paying someone to inspect and clean. Replacing later than their limit would be running an experiment for how much later. Which brings up condition-based maintenance: To be safe about condition-based maintenance you need a specification and limitations to determine condition. Rotax does not provide this, so making up your own limits is, again, experimenting. If you like to experiment, you are welcome in the E-LSA category. The previous engine failure, you mention, obviously had something going wrong that could not be seen and had nothing to do with spark plug or oil changes. Most maintenance or condition inspections do not get inside the engine to inspect for damage, wear, or fatigue. From a purely anecdotal perspective on the oil change, 100 hours at 112 knots typical cruise is almost 13k miles. Many cars are set up for 10k to 12k miles per oil change, which takes between 150 and 300 hours to accomplish, typically. I don't see that being outside convention. For years, everyone said you had to change your oil at 3k miles. This was good advertising by the oil change places and the oil companies to get you to spend money. You will still find people doing it, but there is no technical basis for doing so. Mike Busch mentions most of the aircraft engines fail to make TBO due to corrosion (just sitting). You fly so much, I would not worry about it or going to the Rotax limits.
  13. Time to read Stick and Rudder by Langewiesche...
  • Create New...