Lost track of my fuel in flight again - found economy

[Ed Cesnalis]

The worst thing that happens to me maneuvering in the mountains is to loose track of my fuel and not have it visible when I finally look at the sight tubes.

The first time this happened it was in smooth air with roughly 1 hour of fuel aboard.  While maneuvering I looked at my tubes and both read empty in smooth air.  If you don't know which wingtip the fuel has sloshed to you don't know how to recover beyond coordinated flight to recover fuel from both wings at once.  The period of time when you cannot locate the fuel is not fun

This just happened again, not due to sloshing but due to low light and turbulence.  I had less than 1 hour of fuel and was above critical terrain when I saw no fuel in either tube and didn't know which tube last had fuel

Normally critically low fuel means a proper slip till I land so I can continuously visually monitor remaining fuel until I land.  In this case between the low light, low fuel and turbulence I flew 15 minutes back to the field only seeing 2 empty tubes  

The reason I'm sharing this is that I was shocked that I could return to the field with my throttle very near idle indicating 80kts.  I Flew like this for over 10 minutes well under 4,000RPM at what seemed like 15% throttle.  The engine was reasonably smooth and my economy felt like 100mpg.  I was shocked.

I landed with more than legal reserves, I was fine but not willing to continue if I can't see any fuel and don't know which side remaining fuel is on.  If I had known which side and set up a proper slip in the right direction I would very probably been able to see and monitor remaining fuel and not considering landing vs chute pull.  If you see your last quart  drain out of your empty wing you can still land with engine running and pick your field.  When you don't know which side and can't see it if you do what I did, and run out of gas, it will be a surprise and a field to land in is no longer very likely.

 

[Duane Jefts]

Yikes Ed!  Thanks for sharing.

[FlyingMonkey]

Scary stuff.  do you have tundra wheels?  I do not, and I seem to have one of the faster/slipperier CTs around.  Like you I can maintain 80kt at very low power settings (my downwind setting is 80kt at 3800rpm and 0° flaps), and 100kt at below 5000rpm.

These airplanes are very efficient!

[Ed Cesnalis]

I do have tundra wheels with small wheel pants.

You must have to work on getting flap extension speed.

[FlyingMonkey]

1 hour ago, Ed Cesnalis said:

I do have tundra wheels with small wheel pants.

You must have to work on getting flap extension speed.

Surprisingly the hardest is going from -6° to 0°.  it really doesn't want to slow down at the reflex setting.  If I need to get the flaps down fast I end up chopping the throttle to idle or very low RPM a lot.  

Do you think your custom small wheel pants make you faster than other tundra CTs with the larger pants?

[Ed Cesnalis]

I don't think the wheel pants do a thing aerodynamically.  

I think my CT is fast because my prop is pitched for best speed and not a higher RPM which has become the fashion in recent years.  My habit of flying WOT seems to factor in as well and I'm lighter too.

[FlyingMonkey]

I agree that prop pitch is king for performance on CTs.

[WmInce]

1 hour ago, Ed Cesnalis said:

I don't think the wheel pants do a thing aerodynamically.

I disagree. Based upon my testing, difference was 3-5 KIAS, at various conditions.

[Ed Cesnalis]

2 minutes ago, WmInce said:

I disagree. Based upon my testing, difference was 3-5 KIAS, at various conditions.

faster or slower?

 

My wheel pants are very small and tight fitting.  The standard ones are almost twice the size.

[WmInce]

9 minutes ago, Ed Cesnalis said:

faster or slower?

 

My wheel pants are very small and tight fitting.  The standard ones are almost twice the size.

Slightly faster with pants. But your point is valid between sizes. The big ones have a much bigger profile.