Spin Hop

By lex, on November 5th, 2007

The T-2 Buckeye was not a particularly prepossessing machine, but it was a damned good basic jet trainer.

spin1

It had wide landing gear configuration for safe taxi on the ground, and the straight wings made it reliable and predictable in both up and away flight and the landing configuration. Two side-by-side engines gave you redundancy while minimizing adverse single engine performance. The cockpit was laid out in such a way as to deliver about as much information as a student could be expected to process.

And oh, yeah: You could spin it.  spin2

People who don’t know what a spin is can imagine it as a deep stall combined with a marked yaw rate. Picture a Frisbee thrown in such a way that it’s coming straight down to ground at 6000-8000 feet per minute and you’ve got the notion.

Students tend believe things of their instructors unreflectively, so when we were informed that we’d be going out with senior instructors to spin the T-2 during the basic jet syllabus, we took that information philosophically. None of us, I think, recognized that this was a special instructor qualification, nor that there were very few other jet aircraft – if any – which were deliberately spun as a part of the training syllabus. You see, in most cases, a fully developed spin in a high performance jet is the step just preceding, “Ejection Handle – PULL” in the emergency procedures checklist.

Spins were moderately violent, passingly disorienting and rather a lot of fun. Except for inverted spins. Imagine the previously referenced Frisbee spinning down to earth at 12,000 – 15,000 feet per minute upside down and you’ve got the inverted spin, or most of it. The rest of it was the fact that it tended to an increasingly severe set of negative g spikes as it went downhill. Kind of like falling down the stairs upside down, with the distance between stairs increasing more or less geometrically one to the next. Inverted spins sucked.

I may have mentioned that after earning my “wings of gold,” – and because of the fact that the airlines were hiring people that otherwise would have been jet instructors like they were on sale – I remained in Meridian, Mississippi for 18 months to teach students who were all of 6 to 8 months behind me in the program. I managed to learn a lot along the way, some of it the hard way, while also managing not to kill any students – a signal accomplishment, I’ve always thought.

But some of them tried to kill me.

In flight instructor school it was always drilled into us that it wouldn’t be the bad students who got us killed, but rather the kids with good hands. You never let your guard down with a marginal student, and the “stick limiter” – the instructor’s hand circling the around the controls without quite touching them – was always in effect.

But the good students? They were smooth on the controls, and suave on the radios. They sounded like they knew what they were doing, and always seemed ahead of the jet. You’d let your guard down and they would just barely kill you. Never get comfortable, we told.

Good advice.

Somehow or another towards the end of my instructor tour I managed to worm my way into a teaching seat for the spin syllabus. One day a really good student, kid with a great rep and winning personality briefed with me to go out and fling the jet about through a number of departure maneuvers, stalls, post-stall gyrations and spins. Kid flew the best ever tailslide I ever saw: Three hundred knots on the jet, smooth 4-g pull into the pure vertical, throttles to idle and forward stick to keep the Buckeye from flipping on her back as the airspeed bled off. If you did it perfectly – he did – you’d go straight back down the path you’d come up tail first, and the fuel vapor that had vented out of your tip tanks as the jet slowed to zero would go back through your engines exhaust pipes first, leaving a beautiful swirling pattern as you fell backwards. It was… groovy.

We were having fun, two youngsters wringing a machine out on a lovely Thursday afternoon. When the time came for our first spin, I wasn’t exactly snoozing in the trunk with my oxygen mask dangling, but I wasn’t very far from it in my head. It was to be a straightforward upright spin with me at the controls from the back seat for a demo: 350 kts to 80 degrees nose high, throttles idle and, as the airspeed bled down through 40 kts, full aft stick, full left stick and full right rudder. The jet started a perfect right-hand spin and things were looking lovely, the farm field we’d chosen as our reference point wheeling around and around in front of us even as the altimeter unwound. That’s when the left and right generator lights went on.

Huh, I thought to myself. Both generators?

That’s when the canopy seal deflated and the cockpit de-pressurized, causing our ears to pop. It wasn’t too much longer after that when I scanned the engine instruments and realized that we hadn’t lost the generators – we’d lost the engines. Both of ‘em. We were still spinning down towards the ground and 6000 feet per minute or so. We were just doing it as an unpowered glider. Except for the part that we weren’t actually, you know: Gliding.

This was highly unusual.

First things first, and the first thing was already pretty much complete: Analyze the situation. Second thing was to gain/maintain aircraft control. Already at the controls, I initiated spin recovery procedures, which in the T-2 was pretty much as simple as neutralizing all controls. She fell out of the spin passing about 23,000 feet, comfortably above our mandatory ejection altitude. Pointing more or less straight nose I actually had to wait a time before initiating engine relight procedures, as we were above the safe windmill restart altitude.

Time passes incredibly slowly when you’re pointing straight downhill with both engines out, cabin pressure leaking and nothing really worthwhile to say on the radio or intercomm. Eventually we got back into the restart envelope and I rammed the throttles up to the mil power setting, mashing their associated starter buttons with my gloved hand. Time passes slowly while you wait to see if the motors will relight, but eventually they did.

I figured that we’d seen enough for one day, and – once I was sure everything was back in normal limits – gave the student the jet back for a subdued recovery back at NAS Meridian. Turned out that when I had taken the jet from him for the first spin, he’d put his hand down on the horizontal dash aft of the throttles, next to the flight idle solenoids. Those switches ordinarily kept the throttles from being retarded to the cut off position in flight, but when I’d made my 4-g pull into the vertical, the student’s forearm or wrist pressured them. When I pulled the throttles back to “idle” in the back seat, they had actually gone to “cut off” up front.

It was pretty exciting there for a few moments.

You learn from all of it.

 

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1 Comment

Filed under Best of Neptunus Lex, by lex, Lex, Uncategorized

One response to “Spin Hop

  1. Pingback: Index – The Best of Neptunus Lex | The Lexicans

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