Maybe dumb engine start question

[StevenL757]

11 hours ago, PeteMc said:

Meant to reply to this earlier and got sidetracked...

I actually disagree with your premise.  In the 30 years I've owned my (41 year old) K I have not excessively changed my donuts.  I'm thinking I've changed them once, but the logs  are at the mechanics for the Annual right now.  I've read lots of post from various people and there are as many that say they keep their donuts a long time as there are people that say they have to change them. 

I do think there is more of an issue if you live somewhere that it is really hot.  And I also think a lot has to do with how you land.  I have a friend that makes excellent landings in his Mooney and is extremely consistent.  But he was taught in his primary training to PLANT the plane.  I tend to let the plane stop flying (pending winds, etc.), so I think that may play into it as well.

If you haven’t owned a long-body Mooney, then my observations wouldn’t obviously apply to you as much, however, my point was - generally-speaking - that your disk life is shortened by consistently leaving tanks full or near-full.  All edge cases and exceptions to the rule aside.

I do agree however with your tactic of allowing the airplane to “tell you” when she no longer wants to fly and adjust your flare as needed.

[carusoam]

If your landing skills are really good…

And your runway is really smooth…

You may not notice the rubber donuts stiffening up…

…. Until you taxi across seams and crumbling pavement…

 

it is hard to notice the donuts are worn until they get swapped out for good ones.

Even good donuts don’t make a huge difference in feel…. that would take trailing links and an increase in MGTW…

-a-

[RobertGary1]

21 hours ago, ArtVandelay said:

Doesn’t matter where it sits, dirty oil contains bad things including water. What matters is how the engine was treated. If you check the logs and only see oil changes during the annual, that’s a bad sign.

Eh. Low humidity environments are far less damaging than sitting on the coast.  

[ArtVandelay]

Eh. Low humidity environments are far less damaging than sitting on the coast.  

Maybe to the exterior….

[RobertGary1]

2 hours ago, ArtVandelay said:

Maybe to the exterior….

Mostly to the engine. 

[ArtVandelay]

Mostly to the engine. 

I have a camshaft I use as a door stop in my hangar here in south Florida , the only rust that develops is where there is dirt.
This tells me it’s not just the humidity of the air, it’s the dirt maybe in combination with the humidity.

[PT20J]

Here’s an interesting paper from 1925. The problem is the same, but the oils and metals have likely improved.

44729783.pdf

[A64Pilot]

6 hours ago, PT20J said:

Here’s an interesting paper from 1925. The problem is the same, but the oils and metals have likely improved.

44729783.pdf 339.31 kB · 5 downloads

I have my Wife’s Grandfathers A&P manuals, from I believe the 20’s or maybe 30’s but definitely well before WWII. I don’t believe they were called A&P’s then and he got his rating through correspondence, but it’s actually amazing to see how much was known back then about general maintenance practices, and one difference is in his old manuals they tell you why not to do something, where the modern ones just tell you not to, but don’t explain why not.

Knowing why not is important I think because then you understand the importance 

[carusoam]

3 hours ago, A64Pilot said:

 

Knowing why not is important I think because then you understand the importance 

This act gives you a second method of remembering the step… and gives you a better chance of remembering it correctly…

-a-

[A64Pilot]

I’m back home now so I could take these pictures, these are the manuals and the other photo is showing the component parts of a typical airplane. I don’t know the airplane, is it s Spad? Also in the books it discusses the possibility of vertical flight, a helicopter is postulated.