Warbird Alley Special Feature
"Flying the T-6"
By John "Skipper" Hyle, Associate Editor
Associate Editor Skipper Hyle present a Pilot Report on the venerable North American T-6 Texan (in his case, a Harvard IV), including the story of how he became a warbird owner. |
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Skipper flies his Harvard. |
Flying the T-6 A long time ago, as I was pulling the propellers through on a Lockheed Lodestar, I encountered a hydraulic lock on the left engine. I got some wrenches and pulled the bottom plug. Standing in front of the engine, as I reached around to grab a trash barrel before all the oil gushed out, a friend who thought he was helping me did the unthinkable: he moved the prop. Oil’s a little like blood – a little goes a long way. There was probably no more than half a quart in the engine, but the front of me was covered with oil from about belly-button on down. The flight jacket I was wearing at the time "wore" a lot better after that. The point of this is to tell you how I got my first ride in a T-6. My “helper” that day felt so sorry for what he had done, he gave me an hour of dual in his South African T-6. Now, I had tailwheel time, had owned an Aeronca 11AC, flown Stearmans and Cubs; but had never flown something this big and with this much horsepower. Wow! I was hooked, and after logging a 1.1 hour flight full of of takeoffs, landings and acro, I had to get one. Only one problem. I was a brand new CFI, making the whopping sum of about $9500 per year, and T-6s were selling for the astronomical price of $35,000. (Those were the days.) So I would have to wait. And wait. And wait. Life went on, and after a stint in the Air Force, marriage, an airline job, a son, and making Captain, I could finally afford an airplane again. Except now, two seats weren't enough, and there was talk of needing a fourth. I told my wife that perhaps we should get a C-45. It could carry a lot of kids, coolers, and lawn chairs, and we could still paint it as a warbird and get fuel at airshows. She asked what else I might be looking at. I said a T-6, mainly because it would help me meet the Commemorative Air Force's (CAF) 200-hour requirement to fly their fighters. She asked if it went upside down. I told her all about how it was sort of the T-38 of its day (she’s Air Force, too), and in its day, pilots went from flying T-6s to flying everything from B-17s to P-51s to F4Us. She said I was much easier to live with when I went upside down, and that I should get the T-6. At that point I knew I had chosen wisely. I won’t bore you with the details of shopping – suffice it say, the best piece of advice I got came from Mike O’Hearn of the CAF: Get the best airframe you can; engines can be replaced. So, I ended up with a Canadian Car and Foundry Harvard Mk IV. (You've gotta like an airplane built by people who make railroad cars). I also won’t bore you with the ins and outs of experimental aircraft and Feds that think Harvards have jet engines; that’s for another time. The first flight was 6 July, 1999 at Petersburg, VA. These days, I’ve got what, to some, is a lot of time in the T-6; to others, not so much. The airplane is harder to fly than a P-51. I’ve flown both now, and I never would have never thought that was true. Understand, it’s nothing a competent pilot can’t handle, but the aircraft is the consummate trainer; she demands constant attention to be flown well – just like the T-38 did. Preflight Preflight is nothing special, but you will need a "Snoopy tool" (Dzus tool) to open a couple of panels. Check the cowling well and look for broken angles on the cowl ring – the part attached to the cylinder that keeps the cowling in the proper place. You also need to check for looseness here, as the leather pads will shrink with time. The last thing I check is the oil, after mounting up on the wing. Climb over the rail and have a seat. I find it easier to don the parachute while sitting in the seat than outside. Most of the time, I fly sitting on a chute, but I'll use my travel cushions if I have the room and I'm going a long distance. The aircraft is definitely military. It’s got a roomy cockpit with no floor, and because of this, it should be always be flown while wearing a flight suit – that’s why the pockets are there. If you drop something, it’s a FOD hazard (Foreign Objects/Debris) which can jam the controls and kill you. Take this seriously, and find anything you've dropped before you fly. Bringing the T-6 to Life Strap in and get ready for start. Check the trims at about 10 and 2 o’clock, then grab the wobble pump and start stroking. Once the pressure is up, unlatch the primer and start pumping, while you keep stroking with the other hand. Do not prime with the mixture in idle cut off – all you’re doing is increasing the fire hazard. Depending on the engine and the barrel size of your primer; you’ll need some. Mine starts hot with 2 pumps, cold with 6, and I have a friend who needs 22 cold (no kidding, small barrel plus big engine = twenty-two strokes). Battery – ON. Engage the starter, count 4 blades and turn on the mags. Now you'll find out how well you primed. If you under-primed, the smoke will be blackish. If you over-primed, the amount you did so will be prominently displayed by the size of the fireball going down the right side of the cockpit. If the fire persists, KEEP CRANKING. In today’s world, engines don’t smoke and belch when they start, and people aren’t used to it. When the T-6 was in her prime, that was normal. If the airplane was previously shut down properly, the prop is in "course pitch," as the Brits would say. This prevents the oil needed to lubricate the engine from going straight to the prop barrel. So check the oil pressure. It should come up within 30 seconds; otherwise shut down. Once it’s up and running steady (do NOT move the throttle; Pratt & Whitney didn’t build it that way), you can push the prop to "fine pitch" in keeping with the British flavor, and let her idle at about 1000 RPM until the temperatures come up. One of the most interesting things about warbirds is their variety. The T-6 utilizes a Pratt & Whitney R-1340-AN-1 engine – all of them do. Yet, between the USAAC, USAAF, USN, RAF, and RCAF there are at least 7 sets of operational numbers that I know of. These variances are not just limited to oil temperatures and Manifold Pressure and RPM combinations – they also include airspeeds, flap speeds, and many other numbers. These airplanes all came off the same productions lines, for the most part. It’s amazing what military forces will go through to build pilots. Back to idle. Once the temperatures are where they are supposed to be according to your Dash One, NATOPS, or Pilot Handbook, it's time to taxi. When she starts to pop and belch, they tell me that means you’ve left the prop in coarse pitch. Pull the throttle back, push the prop up, and try again. Understand, that’s just what I’ve been told. I've certainly never experienced this myself. Oh yes, which model do you have? The easiest to taxi by far are the later models, or those subsequently modified to the “P-51” tailwheel. Push the stick forward and it unlocks, pull it back and it locks into a steerable mode that allows 17 degrees of travel. The most difficult ones that I’ve personally taxied are the Navy's SNJ-2s, with a handle on the cockpit sidewall and no, repeat no, steering. This is DC-3 type steering, and I guess it was better in the 1940s, when the Navy's "floating airfields" allowed airplanes to always takeoff into the wind. You’ll have to S-turn to see over the nose, but that’s part of looking cool. Run-up again is normal; consult your manual of choice. Somewhere around 1700 RPM, cycle the mags and the prop. Run the flaps, and DO NOT forget to put them back up. Secure your cockpit – you can fly with the canopy open (another part of looking cool) and it’s windy in there sometimes. Getting Airborne Into position and push it up smartly to 36 inches of Manifold Pressure. Listen to the growl – that’s the 12D40 prop tips going supersonic. Takeoff, unless flying in formation, is done at 36"/2250 RPM. Retract the gear once safely airborne. (Earlier models had a "Power Push," so retraction was two movements; the later models had a Rube Goldberg device that pushed the Power Push for you when you moved the gear or flap levers.) Power back for the climb; manifold pressure first, propeller next. Depending on whether you're single ship or in formation, use 30 or 32 inches, and 2000 RPM. There are lots of moving parts up there in front of you, so be gentle with the power changes, and wait until you're above about 400’ feet. I won’t go into the debate about what to do if the engine quits; just know that the T-6 glides like a brick and weighs about 5,700 pounds. Think about it. Actually, the plane glides better than that, but this is the “square corner” of T-6 flying. Your options are limited shortly after takeoff. The airplane is steady in her environment. I haven’t touched my rudder trim since I owned my airplane, and I don’t advise it. Aerobatics are great, but shut the canopy first. While the various militaries of the world have published many manuals about how to do loops and rolls, there are a couple of basics. I use 140 knots for rolling maneuvers, and 180 knots for "over-the-top" ones. Of course, you can do things slower and not demand anything of the airframe. I’ve rolled at 80 knots indicated, and have gone over-the-top at 140, swearing I’d never make it over. The point is, there’s a way to do proper aerobatics and there’s a way to get the most out of your airframe; both are good to know for that time when you need to change your lift vector and have no airspeed. Don’t spin or snap-roll a T-6. They’re old. A word about the latest Airworthiness Directive (AD) on the wing attach angles: I don’t have the exact statistics but as I understand it, out of some 600 or so airframes inspected, the only cracks found were in the high-time aircraft doing warbird rides and acro. The biggest issue was the corrosion that was found. I suggest the eddy current inspection, as opposed to the dye penetrant – that way, you’ll be sure to find any corrosion on the inside of the angle. For more information, contact the Warbirds of America and the North American Trainer Association (NATA) – these folks are ram-rodding the AD issue with the FAA. One important thought about maneuvering the T-6: When I was a fighter pilot, undergoing training in the AT-38, we were hammered on asymmetric "G"-loads. The concept of "Rolling Gs" is a concept foreign to many people. They are a TREMENDOUS strain on the airframe. For example, the F-16s I flew could take 9 Gs in any Category I load (no bombs, basically), but the asymmetric limit was only 5.5 Gs. We're talking about a modern fighter, built with composites and metallurgy that hadn’t been thought of back in the 1940s. So when you're flying your vintage warbird, set your lift vector and pull. Don't roll and pull at the same time. Let's talk about operating the engine. I won’t go into too many details, as there are many manuals available. Besides acquiring the appropriate manuals for your aircraft model, I would suggest the P&W Manual, circa 1954, on the care and feeding of their radials. John Deakin sells the reprints on his website – I don’t know of any other sources. This book and your manuals will contain various power tables, and will show what settings to use for various percentages of power, etc., etc., etc. My “standard” comes from the U.S. Navy, via Jeff Ethel to Paul Redlich, as published in the NATA magazine. 27 inches and 1750 RPM was considered the “best” combination. With the EGT and CHT I have, I can lean back to about 27 gallons per hour, cruising at about 135 knots. Landing Back to the pattern. Like I said, she’s a military aircraft, so bring it up initial. The Airman’s Information Manual has removed its reference to this type of pattern, and there are many towers and even more uncontrolled fields that have no idea what you’re talking about or doing when you report "initial."They aren’t flying your aircraft, either. And if you are unsure, get some dual instruction from somebody who knows how to do it, and ask Warbirds of America for a copy of the FAA Order that says you can fly up initial and do a 360-degree Overhead Pattern – so the next time a Fed meets you on the ramp, you can explain to them something they should already know. Once on initial, I like to descend from about 500 feet high, 2 miles out, to the break point. This gives me plenty of "smash" through the break. Remember some things: 1). She’s heavy, particularly if you’re loaded with travel gear and a backseater; 2). As we discussed in the asymmetric-G discussion earlier, you should roll to 60 degrees of bank and execute a level pull; 3). If you remember all that stuff you learned for your Private Pilot exam, 2 Gs at 60 degrees of bank is a level turn. You should lose airspeed in the turn; that’s the point. Roll out under 120 knots, and when wings are level, put the gear down. On downwind, once the gear is down, check the indicators. There are several ways to do this on most T-6s. My Harvard Mk IV has all of them – horn, pins, travel indicators, and lights. The only one that counts is the pins – that’s why there's clear plastic over the top of the gear strut. When the gear is down and locked, the male portion of the oleo strut will swing up into the trundle and the locking pin will be pushed forward (by spring or emergency extension) to keep the gear locked down. Check the pins early and check them often. Flaps are at your discretion. Stock airplanes have three flaps, one on each wing and one under the belly. There are airframes out there with the center flap inoperative to keep better flow over the rudder; some have all 3 operative. I never noticed much difference. If the wind isn’t too bad, I use flaps. If I use flaps, I use all 40-degrees worth. That’s the important points about flaps. They don’t really change the speed of the approach for me, but they do change the angle of descent. Three point landing or wheel landing? That’s the question. You should be able to do both, at will. The more the crosswind, the more you should think about a wheel landing. I’ve not been in a ground-loop in a T-6, although in giving dual and formation instruction [where you always wheel land], I’ve come close. The airplane is not any more prone to a ground-loop than any other tailwheel craft, but she is heavy and has a lot of mass up front providing torque. When the tail comes down and the power comes back in a wheel landing, she’s going to the right. That’s why left wings are more expensive. Think back to your Physics 101 class – it can’t be any other way. Once you’re down and under control at normal taxi speed, clear the runway and stop. Then, and only then, reach for the flap handle and retract them. Do not grab the gear handle. There is debate on how the prop control should be used while in the pattern. Uncle Sam said push it up to 2000 RPM in preparation for a possible go-around. That's certainly valid advice – alternatively, you can go around using less than full power. (I don't mean to open that can of worms, I just wanted to point out the two methods.) Shut Down While taxiing in, go through your oil-scavenging technique. Again, even aircraft with the same engine and the same prop have different methods of doing it. Basically, idle the engine to let everything settle (do this at whatever RPM your book says – I use 1200), for whatever time it says (I’ve seen documents that specify anywhere from 30 seconds to 2 minutes), then pull the propeller back to course pitch and wait until the sound changes. If you’re parked in a way that you can see the shadow, you can watch the barrel retract into the cylinder, and that's when you can pull the mixture to idle-cut off and kill the engine. Battery and Generator – Off. Lock the controls to rig for tow. Now, sit for a minute. They built over 15,000 of these things. Think of all the young men that sat in the seat you’re in right now. How many are still around? How many are strapped in their Hellcats at the bottom of the Pacific? How many were aces, and how many never fired a shot in anger? There’s a
lot of history under your seat. Respect it. She’s earned it. |
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