Lesson 57: The big “What if…?”

So…what if your engine stops while you’re flying?

Good question, because it’s been known to happen.  Mac told me that he’s had it happen to him four times over the last 30 years.

The last time John and I did a day fight, we were on the way back from Ramona and he reached over and pulled the throttle back to idle and said, “Your engine just stopped.  What do you do?”

I had had to answer that as part of my pre-solo exam, and I knew that before I got cleared for solo I would have to make sure I knew automatically what to do.  But I wasn’t ready for it that day, and I told John that.

In my last lesson with Mac, though, that’s all we did.

There are two essential phases you go through if your engine stops: (1) Try to re-start it, and (2) if it doesn’t re-start, land the plane.

There are probably a dozen things that can go wrong then you’re flying: engine failures, alternator failures, vacuum failures, fires, and so on.  And for each one, there’s a list of things to do.  Early on, Mac had told me that for the minor contingencies I should just keep some 3 x 5 cards in nearby for reference.  But for the major ones — engine failure, spins — you need to know immediately and without thought what to do.

The problem is, they all get kind of muddled in your head when you’re simply trying to memorize sequences of actions.  “Hmmm…engine failure.  Now, do I check “Fuel Tanks Both” and then push the fuel cutoff valve in, or is it the other way around?”

Fortunately, Mac told me that for the most part the exact sequence for engine failure really doesn’t matter.  Just do all the things with the right hand first — “Fuel tanks both”…”Fuel cutoff valve in”…”Mixture lean”…”Throttle in” — then change hands and do the left hand tasks: “Fuel pump on”…”Master switch on”…”Ignition key on”.  And the engine should start.

So we went through that drill a couple of times, and when you don’t have to think about exact sequencing, it’s actually pretty easy.

But notice I said the engine should start.  What if it doesn’t?

This is where you learn the wonderful glide characteristics of a Cessna 172S.

If you’re up there and the engine has failed and you can’t re-start it, the first thing you do is pull the yoke back and trim it to 65 knots of indicated air speed.  This is the Cessna’s maximum glide speed, which produces about a 9:1 glide ratio.  So what that means is that if you’re at, say 5,300 feet (one mile up), you can glide about nine miles at sea level.  Not too shabby…and the reason they say altitude is your friend.

So after Mac and I had done a few drills of my simulating an engine re-start, we practiced forced landings with a simulated engine failure.

We were in upper San Diego county flying at about 3,500 feet, and near some wealthy private rancher’s airfield that was about 500 feet above sea level.  So I had about 3,000 feet of usable airspace, which was about five miles of glide.

Here’s a Google map showing the airfield. (You might have to zoom either in or out to get the proper sense.)

Mac pulled the throttle back to idle, and we began the drill of assuming the engine was indeed dead.

The first thing I did was trim the plane to 65 knots to get best glide speed.  To do this you turn the trim wheel all the way up until it won’t go anymore, and the plane stabilizes at about 65 knots.  At that speed the stall warning indicator is screaming, but you’re not pulling the nose up any more, so you can more or less ignore it.

And s0 there we were, just gliding along.

The idea is to find a place that looks like a decent landing spot, and start slowly spiraling down, all the while making ongoing determinations about the true desirability of the spot and (hopefully) going somewhere else if you see something that spooks you…like power lines.

So we glided over to the private airfield, and once we got there the first thing I did was align myself with the runway and glide a straight line parallel to it.  What I was trying to do was determine if there was any crosswind pushing me left or right.

There wasn’t that I could tell.

So I started slowly spiraling down…looking, looking.

There were some small ponds on the ranch, and I looked to see if there were any ripples indicating a headwind or tailwind. Nope.  I also looked for trees or shrubs moving.  Nothing.

So I was in luck…no wind.

I kept slowly spiraling until I was about 1,500 feet over the runway, all the time trimmed to 65 knots.  Then at about 1,500, I stopped spiraling, untrimmed the plane, and maneuvered into a regular landing pattern.  And from there it was just like a normal landing: I pushed the nose down to pickup speed and get to my downwind speed of 90 knots, then base at 80 knots, and then final at 70 knots.

For a few moments I thought Mac was actually going to have me land, but at about 50 feet above the ground we went full throttle and got back up in the sky.

And then we did it again.

All in all it was a pretty cool ride, and certainly a confidence builder.  I wouldn’t be so stupid as to say that I can deal with an in-flight engine failure with no problem, but I feel a whole lot better now knowing that I’ve got the sequence of actions for re-start genetically coded, and that under reasonable conditions I can get the plane down safely without power and have a fighting chance landing it.