Pelican’s Perch #40: Psssst! Wanna Trojan?
We’re talking of course, about the North American T-28 “Trojan.” (Why, what were you thinking?) You’ll recall that last month, John Deakin described his checkout in the Grumman F8F “Bearcat.” This time, AVweb’s resident warbird maven invites you along as he qualifies for his FAA Letter of Authorization in the T-28. Although the Trojan has only about half the horsepower of the Bearcat, it’s a considerably more complex airplane. Why, even learning to operate the (hydraulically-actuated) canopy requires a groundschool session. Deak takes you through the highlights of his 14 ground and ten flight sessions with T-28 owner Mark Matye.
We're talking of course, about the North American T-28 "Trojan." This time, AVweb's resident warbird maven invites you along as he qualifies for his FAA Letter of Authorization in the T-28. Although the Trojan has only about half the horsepower of the Bearcat, it's a considerably more complex airplane. Why, even learning to operate the (hydraulically-actuated) canopy requires a groundschool session. Deak takes you through the highlights of his 14 ground and ten flight sessions with T-28 owner Mark Matye.
On Sunday, September 24, 1972, a major disaster killed a bunch of kids, and just about killed the warbird movement, too. An inexperienced pilot attempted to fly a civilian-owned, surplus North American F-86 "Sabrejet" (N275X) without proper training or briefing. The pilot was not aware of (or forgot) the peculiar characteristics of such aircraft, one of which is that if the nose is pulled up too early in the takeoff roll, so much drag is created that the aircraft cannot accelerate very well. This greatly lengthens the takeoff roll, and in extreme cases, may prevent takeoff completely, no matter how much runway is available.
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On takeoff from Sacramento Executive Airport, the pilot tried to "pull it off green," didn't make it out of ground effect, overran the end of the runway, bounced up over a levee, plowed across Freeport Boulevard, and crashed into a crowded Farrell's Ice Cream Parlor, exploding on impact and killing 22 people - 12 children and 10 adults, including two persons in a parked car. Another 25 persons were injured in the catastrophe. One eight-year-old survivor lost nine members of his family - both parents, two brothers, a sister, two grandparents and two cousins. The 36-year-old pilot survived the crash with a broken arm and facial cuts. It was the worst on-ground death toll in California aviation history, and has been known ever since as the "Sacramento Ice Cream Parlor Crash. "
LOAs and LOOAs
Fearful that the FAA might take Draconian action, the EAA, through its Warbirds section, got a small working group together in an attempt to solve the problem without grounding all such aircraft. That group hammered out a new "system," a sort of parallel to the normal FAA pilot certification process. This consisted of "Letters of Authority," (LOA) and "Letters of Operational Authority," (LOOA). The LOA is very similar to a type rating, and the LOOA is somewhat analogous to having a CFI certificate with authority to instruct and recommend people for the LOA.
The FAA and the group recognized that the problem was not the pilots who were already experienced in a number of such aircraft; their primary concern was the fellow with more money than brains, who was able to go buy any toy he wanted, and either go fly it himself without training, or allow some "good old boy" to do so.
Provision was made for those with experience, and initially, any pilot who qualified for five such LOAs could apply for an "Unlimited" LOA. ("Unlimited" does not appear in the regulations; it is an LOA that states "All types and makes of high-performance single- or multiengine piston-powered airplanes." There is no "unlimited" LOA for jets.) Later, the requirement was dropped to three, where it remains today.
As usual, solving one problem created at least one more, and it became obvious that there needed to be some system for getting an LOA in the first place. Yet another sub-group was set up, those with experience in one or more warbirds could get an "LOOA" which allowed them to train and recommend others for the LOA. Only the FAA issues the actual letters, and there are no temporary certificates.
In the end, any experimental aircraft with more than 800 HP or a Vne of more than 250 knots requires that the pilot have an LOA, and an LOOA holder must do the paperwork, the instruction, and the signoff. The guidance for this is found in FAA Order 8700.1 - General Aviation Operations Inspector's Handbook, Chapter 32.
Having the "Unlimited" isn't a license to steal, however. It is still necessary to get a thorough briefing from someone who has an LOOA in the specific airplane, or one of the very rare "Unlimited" LOOAs, and get a logbook endorsement to that effect. This puts the LOOA holder on the spot if something goes wrong, so this is a real requirement.
Here are most of the types covered (the FAA is not good at keeping data like this up-to-date):
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In a previous column, I bragged shamelessly about checking out in the Grumman Bearcat, and in another column a couple of years ago, about flying the Lockheed EC-121 "Warning Star."
That gave me two LOAs, and I began to have visions of getting the "Unlimited" LOA. So, I cast about, looking for an easy way (and cheap, after all, I AM still an airline pilot) to get just one additional LOA. There was also some time pressure, as the FAA is thinking about doing away with the "Unlimited." I mean, after all, if a system works, we might as well break it, right?
The T-28C "Trojan"
Enter Mark Matye, a local businessman and a private pilot with only about 1,200 hours in his logbook. Mark does have a lot of time in some "interesting" aircraft, including the single-seat Pitts Special, which he flew to and in air shows for years. He owns a gorgeous T-28C that he flies a lot, and in which he often gives instruction, mostly to friends. The FAA thought so highly of him, that they issued him an LOOA for the airplane, and he may be the only private pilot in history to hold one!
Since Mark would be the PIC for my training, I needed no "Training LOA," just the dual, and eventually his signoff and recommendation.
At first, frankly, I didn't have a lot of desire to fly the T-28. It's a big, expensive airplane, and while it's very good at converting money into that lovely radial noise, somehow it doesn't have the sex appeal of the Mustangs or the Bearcats. I don't quite know why that is, but I shared the general feeling about the airplane, and smiled at (and used) some of the names like "Toadstool," "Milkstool," "Washing Machine," "Kelvinator Mustang," etc. (Randy Sohn jokes about how he wears a gorilla mask whenever he gets roped into flying one, although gosh, I don't see how that would make any difference.)
At any rate, after talking with Mark, it appeared that this was my best bet to get the third LOA, and then the "unlimited," so we agreed to proceed. It's nice to have friends. He did explain to me, several times, that this would be no "pencil-whip" - that his program had been approved by the FAA, and he fully intended to stick to it. He explained that his program is designed for the average Comanche pilot who wants to buy a T-28 and fly it safely, and he was not about to jeopardize his LOOA by short-cutting the training, either in time flown, or dropping any maneuvers.
This was a little tough to swallow, for I had just finished the program in the Bearcat, and no dual is possible in that single-seat airplane. I felt that, and the T-6 training leading up to it, was more than sufficient preparation for the T-28, and that an hour or two of dual in the milks... er, the T-28 should suffice for a signoff. After all, I didn't intend to solo the airplane, just get the LOA.
Mark was adamant, we were going to do it his way, full shot, or not at all. One of his requirements is that he wants his trainees to be fully qualified to go get his airplane, if he should leave it somewhere and then break a leg or something.
Since it is his LOOA and his airplane, how could I argue? So I grinned and made the best of it - and I'm glad I did, because I ended up learning a lot, in spite of myself. I was also impressed that Mark was not intimidated by my time or experience, and maintained an excellent instructor/trainee relationship at all times. He did not assume that I knew the manual or had studied, and always covered everything in the preflight and postflight briefings. On the other hand, he never treated me like a moron (even if I did deserve such treatment a few times).
The first order of business with any new airplane is always the flight manual, and Mark gave me a reprint of the NATOPS (Naval Air Training and Operating Procedures Standardization Program) manual for the airplane. This was a bit of a surprise, for it is a more complicated airplane than I thought, much more so than the Bearcat, Mustang or T-6. North American apparently intended this to be the primary trainer for the military, a replacement for the North American AT-6 (SNJ to you Navy guys) from which trainees would graduate to the North American F-86, then the top-of-the-line fighter. The "feel" when sitting in the cockpit is very similar, as are many of the systems. Then again, perhaps that's just the North American "company culture."
I should not have been surprised at the complexity or the modernity, for the last Mustang was built in 1946, the Bearcat first flew in 1944, and the first flight of the T-28 was in 1949. The T-28 is indeed a more modern aircraft.
Powerplant
The engine is the much-maligned Wright R-1820, rated at 1,425 HP. It is a single-row radial with only nine cylinders, so more power is extracted from less displacement than many other radials. Some feel this also extracts a price in maintenance and reliability, and Mark shares this feeling. Of course, he pays the bills, so he should know!
Incidentally, the first T-28s ( T-28A) were somewhat underpowered, with only 800 HP, but they do have the advantage today of not requiring an LOA to fly them!
Hydraulics
I was surprised to find the huge sliding canopy is hydraulically actuated. The lever for that is a real mousetrap for the unwary or careless, and Mark is very, very careful to block the beginner from moving it without a careful briefing, a demonstration, and another briefing, followed by another demonstration. Then I was allowed to move it, with Mark leaning into the cockpit, blocking me from disaster. I can see why - the lever (duplicated in both cockpits) has no less than five detents, just to open and close the canopy! The center detent is "Off," or "Neutral," and shuts off hydraulics to the canopy. One detent forward closes it, one detent back opens it. Simple enough, even I got the picture on that. There is also a button on the handle that must be depressed to turn on the hydraulics when canopy movement is desired.
Two detents forward of neutral (the position shown here) unlocks the mechanism entirely, and allows the pilots to slide the canopy in either direction by hand. It's a big, heavy sucker, so I can see why North American chose to power it.
That's four detents. The fifth - two detents to the rear of neutral -blows the canopy violently open with compressed air. There's no interlock or safety of any kind, so it would be very easy to carelessly yank that lever back to open the canopy normally, and go just a wee bit too far into the second detent, and "Thar she blows!" Some maintenance is required to return the system to normal, and Mark threatened to make me do it if I goofed, so I was always a bit wary about opening that canopy! There is also an external canopy handle that will actuate the mechanism by the air bottle, so it is advisable to read the placards, and then read them again.
The T-28 canopy provides a perfect opportunity to embarrass yourself - by taxiing in and shutting down without first opening it. The prop stops, the mag switch is turned off, and you reach for the canopy handle, only to discover that without hydraulics, it's not going anywhere. Whenever that happened to me, I manfully resisted the temptation to just blow it open.
There is a hydraulic speed brake. This is a large barn-door type arrangement on the belly, a big slab with holes in it that drops down into the slipstream for drag. At normal speeds below 200 knots, it's noticeable if you pay attention, but not nearly as draggy as I expected from the size. There are very serious warnings against deploying it above 250 knots, as it will cause a violent pitch up. I didn't try that "feature."
The thumb switch to actuate the speed brake is located on top of the throttle, and the installation is most unfortunate, because in spite of Mark's warnings, I found myself constantly bumping it while moving about the cockpit doing other things. It's not that it's especially touchy, it's just unfortunately positioned and very easy to bump without realizing it. More than once, I found myself with the speed brake where I didn't want it, usually deployed. That switch really needs to be modified, perhaps with some sort of guard.
The gear and flaps are also hydraulic, as is the retraction for the tailhook, which works on this airplane. Pretty normal, except for one thing that made me burst out laughing. Apparently, with the landing gear handle in the UP position, sometimes the handle gets "locked" there by trapped hydraulic pressure. Now THAT is interesting - in the Chinese sense! But even more interesting is the solution. One places the CANOPY handle in the neutral position, and pushes the button on the end of it! Apparently that electrically opens the valve that pressurizes the hydraulic system, which startles the landing gear handle enough to "unlock" it. I suppose the same effect could be had by turning off all electrical power, but neither is very intuitive!
Hydraulics are tied in with electrics, giving rise to some unusual procedures. With all units in the "inflight" position, the hydraulic system is shut down, and fluid just cycles between the reservoir and the engine-driven pump. With any of the components in any other position, the hydraulic system is pressurized by an electrically-actuated valve. (Electrical failure leaves that valve in the "pressurized" position.)
Brakes are a little unusual, in that they take their fluid from a standpipe in the main hydraulic reservoir - but they are not power brakes, just the usual master/slave cylinder arrangement common to general aviation airplanes.
Electrical
The electrical system is more complex than the usual single-engine warbird, with a "monitored" bus that will automatically kick off-line if the generator fails. It is also made more complicated by a system of switches that transfers control of almost all electrical controls between the cockpits.
This transfer switch isn't obvious, but does it ever have a lot of consequences! Most of the WWII-era aircraft had the primary controls in the front cockpit, with just the essentials in the back (and some, like the TBM, not even that!) The T-28 has almost everything in back as well as up front, so North American had to install an elaborate control system that will transfer control to either seat. Perhaps this is where Airbus got the idea for the control switch for the sidestick controllers?
Fuel
The fuel system is blessedly simple - just four bladders, two in each wing, with gravity feed through one-way check valves to a sump tank with a boost pump.
Fuel is either ON or OFF. Now there's a system I can handle! Well, there is one minor complicating factor - the electric boost pump is always on, unless deliberately switched off for testing the engine-driven pump. That's a little odd.
Training
Mark's T-28 course consists of 14 ground-training sessions and ten flight sessions. They are, ah, "thorough." Early on, I realized that most things are covered twice, and some three times or more, and this was after I thought I had studied the manual thoroughly!
Mercifully, there are no hours specified for each session, but the material to be covered is spelled out in great detail. We were able to do the first two ground sessions in one long sitting, another the following night, and two more the following day, for a total of five ground training sessions. We didn't move until Mark was sure I had the picture.
Then we did an afternoon flight. FINALLY, we got to the airplane!
Preflight
Preflight is just like any airplane, but as usual, there are a couple of "special features." For one thing, the top of the wing is nearly six feet up, making mounting the aircraft a difficult chore if the flaps are still up. For this reason, the flaps are always left extended for parking, but for the same turkey who left the canopy closed and shut the airplane down, there is an external flap handle.
Pulling it vents the lines so that the flaps can be pushed down by hand (or by standing on them, from above), creating a ladder of sorts, with two kick-in panels for steps.
It's still a good stretch from the ground to that first step, so Mark thoughtfully provides a small stool for us elderly types. One giant step to the first kick-in step in the flap, then two more to the wing, and one more to climb into the cockpit, which sets high above the wing. This is a TALL airplane.
There is, in addition to the external flap control, an external canopy control. If the canopy is closed before the preflight, the unwary will be severely tempted to power it back with the handle marked for that purpose. Uhhh, nooooo dummy, that handle is for EMERGENCY opening of the canopy, by means of the air bottle!
To open the canopy, one folds out a small, unmarked handhold, and pulls the whole works back. I have not yet blown the canopy, but it would be easy.
I usually go straight to the cockpit, do a setup and check of everything there while standing on the wing leaning in, and I see no reason to do it differently on the T-28. Mags off, trim tabs centered, power on for a light check, chip-detector light test, battery voltage, fuel quantity, controls unlocked, etc., and power off again.
Then walk out on the wing to nearly the tip, and check the fuel quantity visually, secure the fuel cap and cover, and do a quick check of a couple inspection holes on top of the wing. I like to took at the tops and bottoms of wings for wrinkles, and that's a really good idea on this airplane, because to my shocked surprise, it is NOT a high-G airplane, being limited to only 4.0G.
One possible reason for this is the large "notch" cut into the belly for the access hatch. That has to take away a lot of structural strength that would be present with longitudinal members there instead. I looked for wrinkles in the fuselage around the notch, too!
All radials tend to accumulate oil in the bottom of the case, and many operators install separate electrically-powered scavenging systems to suck all the oil out, sometime after shutdown. Mark has this system, and also has a "pre-oiler," which will pressurize the engine oil system before starting, assuring early lubrication to critical parts. I know of no real data to support the efficacy of this, but it sure seems like a good idea.
It's a big, roomy cockpit, so I didn't have any trouble strapping in and getting organized, unlike the tiny Bearcat. This is a MAN'S airplane, not built around a runt!
Startup
Startup is conventional for the big radials, boost pump on, mixture "Idle Cutoff," shoot the fuel in with the primer to the blower area, and control the air with the throttle. By far the best way to start, with this type of primer. Once the engine is running smoothly on prime alone, oil pressure up, the mixture is placed in "Rich" ("Auto-Rich," or "Normal" in some), and when the engine floods from too much fuel, the primer is released. The short stacks do their job of converting gas to noise very effectively, even at idle.
It came time to move out, so I listened to the ATIS, promptly forgot the code letter (I'm bad about that, should write it down), and just before keying the mike, asked, "Hey Mark, did you catch the ATIS code?"
"Yes."
(Silence)
"Uhhh, are you going to tell me?"
"No."
For a split second, I'm sure the steam started coming out of my ears, but then I busted out laughing, retuned the stupid ATIS, got the code, and this time managed to remember it long enough to tell ground control. Good lesson, and y'know what? I haven't done that since. We were both laughing all the way to the runway, that day. In fact, we laughed a lot through the whole training program, there's no FAA prohibition that one can't enjoy this sort of thing - yet.
Runup is at the usual 1700, a couple of prop cycles, then a power check at field barometric manifold pressure, a mag check, flip the electric boost off momentarily to check the engine-driven pump, back on, run the checklist, and done.
Flight Characteristics
With roughly the same weight and power of a Mustang, acceleration is very quick, and acceleration to 150 knots is effortless, even with a hefty climb angle. No, it's not a Learjet, but ever so much more satisfying, somehow.
It is very light on the controls, and has no unfriendly characteristics at all. It does require more trimming and constant re-trimming in all three axes than any other airplane I can remember, although the Mustang comes close. If your left hand isn't doing something, it is usually resting on the three trim wheels.
The heel of the hand can be used for roll trim, the fingers for the rudder, and the thumb for pitch. It's almost like a helicopter, if anything changes at all, all three trims change. I'm not much of a "fiddler" in any cockpit, but the T-28 lets you know right away when it's not happy with the trim setting. It's a good idea to preset about five units of right rudder trim before takeoff, because that's just about what you'll want right after the gear is up. I deliberately tried one takeoff with the rudder trim centered, and didn't notice any difference on the takeoff, but sure enough, as we stabilized in the climb, I had to reach over and crank in about five units.
The first "lesson" went well enough that Mark combined two in the same flight, for three takeoffs and landings, numerous configuration changes, slow flight, landing and go-around procedures, a total of 1.7 hours. We broke for a bite, reviewed the ground training sessions, briefed for the next flight, and launched late in the afternoon for another 1.6 hours.
And so it went, a ground training session and/or review, flight training, debriefing, and very often a review of prior work. At five hours, we began working on emergencies and abnormals, then recovery from unusual attitudes (VERY unusual attitudes!), spins, and forced landings.
Some extra time was used in hopping over the hills to the area west of Willy J. Fox Field (Lancaster), as Mark prefers the wide open spaces, flat terrain, and numerous landing sites there, as well as separation from airways for aerobatics. He's absolutely right, and I am ashamed to admit that I have not always been so scrupulous in avoiding airways when belly up.
G-LOC
One of the areas where caution is needed with all these airplanes is speed in the vertical descent. It builds at truly awesome rates, and can eat up many thousands of feet of altitude in a hurry. Recovery can often mean pulling more Gs than you might want with older airplanes, and that's even worse with older pilots! There have been a number of fatal accidents at airshows from this in recent years, it's a very easy thing to misjudge, and a very small difference in entry altitude, speed, and "pull" can make a very large difference in the altitude at recovery.
We were having fun with this at 12,000 feet, pulling up to the 45-degree climb, rolling inverted, and pulling over the top, then right on through the bottom of a loop, right up to the 45-degree climb again, letting the speed bleed off, and repeating in rapid succession. We were experimenting with various combinations of attitude and speed going "over the top," noting the speed gained, and altitude lost. It's an interesting maneuver, throughout. At the top, below 100 knots, it's very easy to pull a wee bit too hard, and get a positive-G stall, inverted. This can even be a less-than-1G stall, if you get slow enough. Pulling too hard coming down vertically can easily get into an accelerated, high-speed stall, recognizable by a harsh shudder. Relaxing just the tiniest bit of back pressure solves that. But the more you pull, the greater the G, and the more drag, which prevents excessive speed. It's a lovely exercise in energy management with rapidly changing parameters.
One thing you really don't want to do is pull much power off, because not only is that very hard on any radial engine (prop driving the engine, a real no-no), but in many airplanes, the prop disc can create so much turbulence that it blanks out the tail, and reduces control effectiveness.
We did about six of these in rapid succession, and I had been tensing my legs and gut before each one to resist the 4.0 Gs we were pulling. At about number three, I got behind, didn't tense up properly or early enough, and noticed the familiar "gray-out," normally not a problem. We pressed on, and I can remember that on each successive one, I was a bit further behind on tensing up my tummy and leg muscles, and each time things got a little worse. Oddly enough, the worse it got, the less I seemed to care. On the final one, I don't remember a thing after the vertical descent. Mark said it all looked normal, and my control inputs were normal, and we ended up in the 45 upline again, upright. I do remember just sort of drifting mentally, daydreaming, thinking of something else entirely outside flying. Then it seemed as if I was dreaming about flying "something," then it slowly seemed as if I was dreaming about flying a T-28. I became aware of Mark saying "Ok, get your nose down." "John, get your nose down." I didn't seem to be able to figure it out, but I was able to say, "Mark, take the airplane." He didn't get it the first time, perhaps I mumbled, but I repeated, "Mark, take the airplane!" He did, then dropped the nose to level, and within a few seconds I was back to fully normal, and took the airplane back.
"What's the matter?"
"I don't know, I got really disoriented there, for the last half of that."
Then I realized I'd just had my first case of "G-LOC," for "G-induced Loss of Consciousness!" Pilots have long known about "grey-out," and "blackout," from G loading ("Red-out" from inverted loads), but G-LOC has only become well understood in recent years.
A glance at the recording G-meter told me that I had done so at under 4.0G! I was mortified, had NEVER done that before, even at much higher loadings, in much wilder aerobatics.
What really shamed me was the realization that Mark had not suffered at all (or at least he said he didn't!)
In thinking it over, I came to a number of conclusions as to why this happened, this time. Some will sound like excuses, so be it.
I'm 61, and Mark is about ten years younger. He appears to be pretty fit and muscular, I'm 40 pounds overweight. I walk and run a lot, but the only upper body work I get is typing, which doesn't help with resisting Gs. Finally, I was not using oxygen at 12,000 feet, Mark was. I was not previously aware that makes a difference, but the literature I've read since strongly suggests that it does. I suppose I'm going to have to quit being a cheap airline pilot, and go ahead and pop for a full-face mask. The rapid rate of repetition, with no time in between for recovery, and my losing track of when to tense up didn't help. What a lesson!
Trojan-Qualified!
The final session was a good review of everything, plus a landing after a simulated engine failure, zero flap landings and other system failures, pretty much a final check ride.
Mark wrote the letter recommending me for the T-28 LOA, and with that LOA in hand, the Seattle FSDO was kind enough to issue the "Unlimited" LOA.
Could this have been done in less time, for less money? Sure. I'm sure there's someplace where I could have studied the manual, gotten a good solid briefing, flown the airplane for an hour or three, and been signed off, complying with the rules, satisfying the FAA, and ending up safe enough. Even Mark admits that.
But Mark has a unique designation, and apparently the FAA has made it abundantly clear to him to if he doesn't stick to his plan for everyone, that designation can and will be taken away. I respect that, and I respect him for playing it straight. He is also a superb flight instructor, one of the best I've ever flown with, anywhere. His instructions are clear, correct and to the point, and repeated just enough to get the point home. He stays off the controls and out of the way in the air, and mostly keeps quiet until the maneuver is done, then he might have a very few well-chosen words of help, but most of the instruction will be done on the ground. Somewhere, he has learned to teach in a most effective way. I hope he gets the CFI, this business can use more like him.
Epilogue
There was a neat twist to the story. Mark was all set to take his Commercial check ride in his T-28, with an FAA Inspector from the Van Nuys FSDO, one Gary Hunt. Gary has extensive worldwide experience in many types of "strange" aircraft, loves the old warbirds, and has been supportive and helpful. But when the time came for Mark to take his check, Gary was out of town for some indeterminate period of time, and no one knew when he'd return. No other FAA types would touch the deal with a ten-foot pole, so Mark was despondent, figuring he'd have to go rent a 182 or something, learn to fly it, and then take the check in that. He'd found a young local CFI, Jeff Caruana, who had flown with him a lot in the T-28, getting him ready for the ride, and didn't want to have to start all over again.
Through the tender mercies of the Seattle FSDO and Inspector Dave Lehman (my POI there) and the very nice cooperation of the Riverside FSDO, I was able to get special permission to do his ride in the T-28, on a one-time basis. Mark was as nervous as they get, for this was only the second check ride he's ever had, and his private was in 1983. He was nearly a basket case when we sat down to do the oral, which I began with, "Now, you remember when you wouldn't tell me the ATIS code…"
He did an absolutely superb job, and now has the temporary in his pocket. If you'd like to fly a T-28, I can't think of a better place.
Be careful up there!