Check Density Altitude

By lex, on July 17th, 2009

It was a lovely change of command ceremony, one of my favorite people in the world gave up the 125th Strike Fighter Squadron at the end of an arduous 18 months in battery. Chilly has the three q’s: High q (dynamic energy), high IQ and high quality. Unlike many men in his position, he left attendance to his ceremony to the discretion of his people, declining to force them into ranks on a hot summer’s day. That was a nice gesture, I thought – they can read the plan of the day on Monday, if they missed the news.

He said a few kind words about your humble scribe as he gave his speech, summat to do with being a mentor when such were few on the ground, but the fact of the matter is that yer man is one of those fellers junior to you that make you understand your own limitations. I knew him when he was a lieutenant and I was an O-4, and he hasn’t changed all that much in the intervening time, command at sea and bonus command notwithstanding.

Check Density Altitude.jpg

He didn’t need to change all that much.

Off to Tampa now with his long suffering and their clan, for to tighten up the SOCCOM folks. Who’d better get ready for some heavy rolls.

‘Twas a fair bit to go for an hour long ceremony in the middle of July in the San Joaquin Valley. Wouldna been another couple I’d have made it for, but hizzoner and his lady are that special.

Hot and getting hotter as I headed out to the aerodrome. The left magneto was playing the fool at the hold short, dropping off nearly 300 RPM when tested, and running her rough. I leaned her out a fair bit with the cowl flaps open and burned the plugs clear at 1800 RPM, which did the trick of letting me get home rather than asking for services at the local FBO.

The Flight Service Station briefer noted that it was 33° C on the ramp, and that I’d be advised to check density altitude. The airport itself is only a couple of hundred feet high, the strip 5000 feet long, the surrounding terrain unremarkable and we left 20 gallons of fuel in the tanker for the two hour flight back south. I wasn’t much concerned. At least, not until the trees at the departure end came into clear view, as they’re wont to do when you’re fretting over a fouled plug.

I’m still not that accustomed to taking off from a non-towered airport. You call in the blind to whomever might be listening in and hope that anyone planning to land as you’re taking off will notice. Somehow it feels like cheating, taxiing around and taking off without a by-your-leave. I reckon you get used to it after a bit.

The Cardinal scoots along pretty well for only 200 horses under the cowl, but she’s no banshee in the climb. Seven hundred feet per minute or so when the wheels come up and the flaps are stowed, but it trails off to 500 FPM or so all the way to 9500 feet, which was right for direction to cross the Tejon Pass southbound. I still get a little quilty over rough terrain in a non-turbocharged, single engine piston. That doesn’t have an ejection seat. When you’re flying a single engine prop job, you supposed to be on constant lookout for a place to put her down should the spinner quit. There’s about a ten minute window flying over the mountains north of LA where you’d do just as well to keep your eyes shut.

LA Approach showed every semblance of happiness to clear me through the Class B on the Shoreline Route, so long as I conformed to the profile.The Cardinal’s Lycoming engine hummed along like a sewing machine, delightfully ignorant of the terrain contours below.

Managing heat in the tightly cowled engine is a bit of a trial: We’re taught to pull no more than 1″ of manifold pressure per minute to avoid warping the engine block, but of course the MP increases as density altitude decreases in the descent, so you’re right back where you started when the minute hand comes round. Somehow we got her down below Sandy Eggo’s Class B and into the pattern for a successful landing.

Lots of folks talk about the Cardinal “crow hop”, which apparently comes when an over-eager 172 driver tries to force her on deck when she’s carrying too much smack. All well and good in a Skyhawk, but the Cardinal has a stabilator rather than an elevator, and dumping the nose apparently can lead to some pretty wild rides. I’ve got many more hours flying stabilator aircraft than 172s, so – thus far at least – patience has been my unaccustomed virtue. Set the landing attitude with idle power, and she pretty much has to land. Eventually. Flaps up to put the weight back on the wheels, cowl flaps open as the windstream dies down, IFF standby and ask Ground Control for clearance back to the line.

I’m no longer climbing out in max grunt with the VSI pegged and a half a g unload to level off by 6000 feet without blowing through the altitude restriction. I don’t have a moving map between my legs driven by a GPS-aided INS. Can’t take potshots at passing airliner traffic in sim mode and watch the air-to-air missle time-to-go counter tic down.

But I went flying today, and that’s not nothing.

Which I’ll be reminded of when the bill comes due.

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Filed under Best of Neptunus Lex, by lex, Carroll "Lex" LeFon, Carroll LeFon, Flying, Lex, Naval Aviation, Navy, Politics and Culture

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