Learn from my dumb mistake

[nworth]

Went flying today -- just some airwork and fun flying. Hadn't practiced (real) slow flight in a while. It's summertime here in Florida and getting hot and the normal midday early summer cumulus were getting going with probably 75% coverage above 3500 feet. However, I found an open spot midway across the state so I decided to climb up through the hole. Got up to about 5500, on top of most of white stuff and started playing around with steep turns, "falling leaf" maneuvers and just flying along as slow I could (on the front side of the power curve) while continuing to marvel about how the 260se performs.

Of course, during all of this, I had a little power in, between 14-16 inches and the mixture control was maybe 1 inch back. When I was done, I decided to head to my favorite uncontrolled airport for some landing practice. So I tipped her over, pulled back the throttle a bit and...the sound of silence.

Yup, a windmilling prop....

A quick look down through the "hole" showed lots of farmland. Possibly somewhat swampy but lots of open space at least.

I'm strangely calm.

Ok, mixture in. Sequence mags 1 and 2. Throttle in and out. Check tank valve.

No, no, no and no.

Starting to set up for best glide and then I try pulling mixture out.

Pup, pup, pup and the engine comes back alive. A bit of sputtering, but ok.

Hmmmm. What happened? Let's definitely head toward that nearby airfield and see what's up.

As I descend, the engine gets happier and happier. I am beginning to relax. I see the airfield, enter the pattern, land well (even though my hands were shaking a bit) and decide I had not leaned the engine well enough during my slow speed airwork at altitude. So, "on the go", I push the throttle forward and off I am with my touch-n-go. I notice a little sputter but nothing to be concerned about.

A couple more touch-n-goes and my concern is beginning to fade. I head back to home base, land on the long runway and taxi fast because I know there's a King Air on short final behind. As I clear the runway and pull back the throttle, the engine stalls (!!!!).

I call ground, tell them that I might be sitting here a bit and try to figure out what's what. (I eventually do get the plane started and taxi to the hanger...)

Anybody want to hazard a guess as to what dumb thing I did????

[kwmoore]

Anybody want to hazard a guess as to what dumb thing I did????
Definitely a guess, but it sounds like a too-rich or even flooded engine to me. Did you inadvertently knock the fuel pump switch to the low boost position?

This happened to me once while in the pattern and I only discovered it when the engine quit on the taxiway. Thankfully I had carried some power through the approach and flare all the way to touchdown, otherwise the engine might have quit at a most inopportune moment. :eek: It restarted when I pulled the mixture to full lean, cranked, then enriched when it started.

[nworth]

Definitely a guess, but it sounds like a too-rich or even flooded engine to me. Did you inadvertently knock the fuel pump switch to the low boost position?
Jeeez, I was hoping to baffle the group for a few days at least!!!

Yup, reconstructing this, I had flipped the fuel pump to high on departure from the home airport when the #1 CHT hit 385. I turned the pump to "off" a few seconds later.

What I apparently really did was flip the switch right through the center off position to the down "low" position. The switch in my plane does not have a very distinct detent so this is all too easy to do.

The location of the switch, low on the left panel and mostly obscured by the yoke, makes it difficult to tell the position by visual inspection.

Leaving the switch on low is not really a problem on climb out if, as I do, you lean to a particular EGT value. Perhaps I should have noticed the mixture control was further out than usual, but given the heat of the Florida summer, there can be a significant difference in density altitude hour to hour so I usually don't really pay attention to this.

During the maneuvers at altitude, there was enough throttle to mask the problem. Only when I pulled throttle back did the flooding shut down the engine. Of course, as I descended the increase in manifold pressure basically "solved" the problem.

When doing the touch-n-goes and when finally landing at my home airport (and during the fast taxi after), there was enough throttle to mask the problem. Until, I finally pulled throttle entirely after clearing the runway...

As you noted, all this is worrisome if, for some reason, you need to pull throttle all the way out near to the ground.

[n2099x]

Yep, that would have been my guess also, been there done that. I bumped mine to low during a mag check. Then I caught it on climb out when I started leaning.

Glen