Flight test: F4U-5NL Corsair
- Credit: Archant
Corsair dream… come true: the wickedly powerful naval night fighter that now belongs to the man who admired it as a boy | Words Maxi Gainza - Photos Matthias Dorst
In flight, the Corsair is graceful and sinister at the same time, its kinked wings touched with the elegance of a double-jointed swan, while the long blunt nose and sky-rending engine growl conjure a Jurassic avian bent on the kill.
On the ground and up close - especially in fading twilight when the imagination stirs, and with folded wings to enhance its hulking presence - it exudes the ornery menace of an otherworldly bouncer at the celestial gates to Valhalla.
The four-bladed propeller is 13 feet 2 inches in diameter (two feet wider than a Mustang's). That's what it takes to harness the 2,400hp of the Pratt & Whitney R2800 double-row eighteen-cylinder engine lurking under the cowling.
It is also the reason for those inverted gull wings, to minimise the risk of tip strike on takeoff without the need for a taller and hence weaker undercarriage. The leg oleos are squashed to a fraction of an inch, intimating the weight they carry on the ground. The massive flaps, normally left extended on the ground, do the rest.
Scaling up the Corsair's steep flank to the cockpit via wide-set, spring-loaded steps and hand-holds cut into the skin, you need the agility of a rock climber and a head for heights.
The fuselage panels are spot-welded, this being an entirely original Chance-Vought F4U-5NL model. The skin is surpassingly smooth and strong?to the point of resisting desperate axe-blows in a failed attempt to extricate a pilot downed behind enemy lines in Korea.
- 1 Civilian instructor qualifies as military QFI
- 2 Irish Air Corps to train in the US
- 3 Flight test: DHC-1 Chipmunk T.10
Once inside, the roomy cockpit is dark as the Grim Reaper's cloak, except for the floorboards, with black-on-black instruments and a bewildering array of switches and vital levers running both sides of the seat further back than your elbows for want of space up front.
Looking through the armoured windscreen the intimidating propeller blades seem almost normal, but only because shrunk by the perspective of its stonking bazooka nose.
Strapping to my giddy perch ten feet off the ground there is little of the loin-girding excitement I get when buckling up in a Mustang or a Spitfire. At least not for this my first flight. I feel instead as if I'm sitting in judgement, loftily, god-like, of everything I behold?not that I can see much with the wings folded over the canopy and the nose blocking the view ahead.
Perhaps sitting in judgement at my own presumption, an over-the-hill PPL with no formal military training (albeit with some time on Yaks, Spitfires and Mustangs) wanting to fly a plane with such fearsome mass and power and?potentially, since we are unarmed?such devastating punch at my fingertips. The urge to climb down and go for a coffee hits me... How come I've let myself in for this?
Blame the boy?the boy I was when I first set eyes on this same dash-5 Corsair in Argentina. It then stood forlornly on a plinth outside the Aviation Museum in Tigre on the outskirts of Buenos Aires, its midnight-blue streaked and faded by long exposure to the elements.
My immediate and lasting impression was that only gods could fly such a hunk, never mind land it on a pitching straight-decked aircraft carrier, as indeed it had while serving on the A.R.A. Independencia, Argentina's sole carrier (formerly HMS Warrior) and, prior to that, flying night combat missions in Korea while attached to the US Marine Corps VF513 squadron, famously dubbed the 'Flying Nightmares'.
Fast-forward to 1994. Thanks to two resourceful Frenchmen, this same Corsair was bought off the Argentine Navy and shipped to France for a thorough overhaul, during which the wing-mounted radar nacelle was removed, thus improving stalling behaviour, and the original supercharger cheek intakes at the sides of the nose cowling were replaced by the chin-mounted carburettor scoop of an F4U-7, as operated by the French Navy in Indochina and up until the Algerian conflict.
Resprayed in Aeronavale colours, it subsequently enjoyed a new lease of life being displayed across Europe in the virtuoso hands of Ramon Josa, a consummate former French Corsair carrier pilot?godly indeed were it not for his warm humanity and sense of humour.
Until, by a happy alignment of stars, and as if to prove my view that aeroplanes choose their owners, it had ended up in my hands, jointly bought by Meiermotors and Max Alpha and now based in Bremgarten. To complete the circle, we had its original dash-5 intake cowlings put back and had it resprayed in its Korean War anti-glare flat-black paint and red-letter markings.
Little if any corrosion was found during overhaul in France?Chance-Vought didn't cut corners protecting its carrier-borne aircraft from the sea air?so the Corsair I'm now strapped into (rather than gawping at from the ground, in my short trousers) is much the same as when US Marine pilots braved Chinese flak and diced with cables strung in their path across narrow mountain passes while conducting low-level operations, mostly in the dark.
Big boots to fill. But, over the phone and in person these last weeks, Ramon has talked me through every aspect of handling a Corsair. Achim Meier, who's already done a few trips in it, has shared his own impressions while showing me around the airframe in detail.
I have sat in the cockpit more times than I can remember, pilot handbook and checklists in hand, and also taxied it out yesterday just for an engine run, always a good exercise before soloing a single-seat warbird. I have sore calf muscles and biceps to remind me of how hard I had to stand on the toe-brakes and hold the stick back against the propeller slipstream on the elevators to hold the tail down and not creep forward while opening up to a mere 28 inches manifold. So no more excuses...
By now I am sufficiently familiar with the cockpit to appreciate its well-reasoned layout, and the reassuring redundancy of its systems. The engine instruments are placed to the left and below the standard flying ones, the unusually wide forward instrument panel allowing for this, so no left-right eye flicking is necessary during busy moments, as is usually the case.
The throttle, propeller and mixture control levers on the left shelf are neatly lined up, the vertical-grip throttle being the tallest. Next to it but slightly behind is the flap lever. It has 10° detents down to 50°.
Flaps are hydraulically operated, as are indeed the undercarriage, wing-folding, brakes, oil cooler doors, and tail-hook operation - even the canopy slides open and shut on hydraulic juice. In the rare event of a complete hydraulic failure (the Corsair having an emergency electrically-powered hydraulic back-up) you shift a small latch at the 50° full-flap mark that isolates the flaps' hydraulic circuit from other hydraulic sub-systems and allows them to be blown fully down by an 1,800psi charge of compressed air at speeds lower than 110 knots.
The brakes have independent hydraulic units so will carry on working if elsewhere hydraulic power is lost. As for the undercarriage, if both the main engine-driven and emergency hydraulic pumps fail it can still be lowered on compressed air, again at speeds below 110 knots, as can the canopy on its own air bottle.
Immediately behind the power levers are three lined-up toggle switches for oil cooler doors, carburettor heating and cowl flaps (the latter electrically driven) all within easy reach of your throttle hand. And just behind these are the trim tabs, seven in all and electrically actuated. A mini-joystick controls pitch and roll, as in many early jets, while a horizontally-laid toggle switch operates the rudder trim.
There is a guarded trim-override switch next to these to deactivate the system in the event of runaway trim, after which you can still compensate for pitch and roll via four small press-down switches?again, similar to the Hawker Hunter's?the whole lot at your fingertips.
The auxiliary fuel pump switch sits outboard of the rudder trim. Slide your hand further back and you hit the fuel tank selector, and still further back (easier to feel than see) the drop tanks and emergency bomb-release lever, and the g-suit connector?all inoperative today. But in between the latter two is the tailwheel lock which is truly vital. Forget to lock it for takeoff and landing and it will most likely ruin your day.
The ignition and engine-priming switches sit just above the right console next to the battery/generator three-position switch, and above these the volt-ammeter and auxiliary hydraulic pump switch.
Inboard of these is the arrestor hook lever sticking out in its 'up' position as conspicuously as the undercarriage's on the opposite side. The hook is mechanically-linked with the undercarriage, so if needed you must make sure to select it 'down' before lowering the wheels.
On the right-hand shelf proper are the circuit-breaker panel (moved from its original and hard-to-see position on the shelf's wall below knee-height), oxygen indicators, comms selector, pre-oiler switch, and a mix of original and modern avionics controls. And farthest back, the all-important wing-folding lever, tucked behind your elbow.
Achim is already up, leaning over the low canopy sill, toes stuck precariously into a foothold a fair bone-busting height off the ground, while Felix our engineer has plugged in the ground power trolley and moved forward to a prudent distance with a fire-extinguisher close to hand.
Achim's calm, to-the-point manner is welcome as I gather my wits in order to conduct the Wagnerian overture involved in kicking eighteen cylinders guzzling a grand total of 48 litres of fuel/air mix into life.
The engine is a newly zero-houred P&W 2800CB from Anderson in the USA, with only a few hours on the Hobbs since recently installed. It runs extremely well, so Achim tells me, consuming less than a litre of oil per hour?a rarity amongst radials of such size.
The odds couldn't be better stacked in my favour, so here we go.
Pre-oil for two minutes to lubricate the cams; then crank eighteen blades with the magnetos off to clear out the engine. (We've already pulled it through on the ground to check for hydraulicing, a two-man job and quite a workout.)
Boost pump on: prime for eight seconds, throttle closed, then turn off the boost pump again. Cowl flap switch on 'automatic', same for the oil cooler door; mixture at idle cut-off, prop lever forward to full 'increase'; open throttle a smidgen?about 3 to 4mm?and reengage the starter. Count four blades turning in the right direction, and switch both mags to 'on' while continuing to prime.
Far ahead the engine begins to cough on the odd cylinder, blowing back puffs of white smoke, picks a few more at random, stumbles, pulls itself up, mustering ever more pots while?prompted by Achim?I continue to prime judiciously, leaving the throttle as is (playing it would flood the engine, dangerously).
The ragged firing steadies into a distant barrage, punctuated by insistent vraap-vraaps drumming down the fuselage and whipping back copious smoke, gradually clearing as the engine settles into a full-bodied chuggety-chug.
Only now do I let go the primer and move the mixture to 'auto-rich', then nudge the throttle forward a fraction to 800rpm to even out the engine note and goose the hydraulic pressure. Ts and Ps normal?we are in business.
But first deploy the wings! Checking that hydraulic pressure is up, and twisting around and reaching back, I pull the requisite lever forward to the 'spread' position. Sunlight floods into the cockpit and the cavernous basso profundo of the propeller slipstream bouncing off the folded wing panels fades as these descend and deploy.
Now I shift the lever outboard into the 'lock' position, keeping a beady eye on the wing-mounted tell-tales as they sink flush with the surface to confirm that the wing hinge pins have slid through their locking eyes.
Felix can now reach up to remove the pitot head cover, and Achim signals me to recycle the wing folding, just in case. Satisfied, Felix disconnects the ground trolley and I move the power switch over to 'battery/generator'. Taking a big breath, I give the Tower a call, flash my best false-confident smile at my crew mates and assembled onlookers and taxi out.
The momentum of that long, heavy nose is huge as I weave it slightly to look ahead. It also dips alarmingly at anything but a gentle, progressive pressure on the brakes, aggravated no doubt by my high vantage point which tends to make one taxi faster?it's worth keeping an eye on the GPS ground speed readout.
But yesterday's little exercise has alerted me to this and taught me how much to anticipate the swings and finesse the brakes. Otherwise, the Corsair rolls very stably on its wide undercarriage.
Warming up 32 US gallons of oil takes a while, especially with a radial, so at the hold I have to wait about five minutes, feet hard on the toe-brakes even at a mere 1,000rpm and stick held back, while oil and cylinder-head temperatures creep up to the green arc.
When at last I can open to thirty inches manifold for mags and propeller checks I'm in a lather, thighs and calf muscles on fire from straining on the brakes like a rugby forward stuck into an unending scrum, and barely able to hold back the stick with one arm against the gale pounding the elevators while I reach with my left hand to test the mag drop and the propeller cycling. It's therefore more with relief than anxiety that having completed the run-up I enter and line up on the runway.
Quick glance at the shortened takeoff checklist placarded on the instrument panel?tabs set, (pitch a touch nose-heavy on the indicators, ailerons neutral and 5° right rudder); flaps up; wings down and locked (obviously); fuel on: mixture auto-rich; propeller fully fine; harness secured and locked; boost pump on.
I roll forward a bit with centralised rudder to lock the tailwheel, lightly tapping the rudders to make double-sure it has. Checklist complete.
Today the wind is light and almost down the runway. I open the throttle smoothly and gradually, and soon I'm engulfed in a creamy roar as we gather speed. I use peripheral vision to keep straight on Bremgarten's wide runway, but as I fly the tail up passing 35-40 knots I catch sight of it beyond the nose, centre-line flashing under.
Big surprise: there is far less gyroscopic precession than I'd anticipated from the massive prop as we transitioned from tail-low to flying attitude and the torque is easily contained, maybe a lot of it absorbed by the sheer mass of this aircraft.
Well, I'm also not shoving in the power like those young red-blooded naval aviators lifting a max-loaded Corsair off a carrier's deck would have done. There isn't a war on, and I have oodles of concrete ahead.
Pushing through 45 inches manifold and 2,800rpm we don't tear along like a Mustang, never mind a Yak-3, but rather accelerate in a trundling way and lift effortlessly before reaching 100 knots and the recommended fifty inches, the wheels lingering on the ground a heartbeat longer while the long-stroke oleos extend to their stops.
It's a very smooth rotation, those generous, slope-shouldered wings making light work of hauling our 5,300kg into the air and establishing us in a positive climb. I remember to tap the brakes to stop wheel spin before reaching for the gear lever.
Below my wings, the sturdy undercarrige legs (so strong they can be used as dive brakes up to 300 knots!) fold backwards, wheels rotating 90° to fit flush in the wells, but not before a heavy-duty cable on each leg has pulled the oleos in as far as when the plane sits on the ground so that they do fit. Should it snap in the process, you will end with a hung gear but?as I recall?each cable has a breaking point of over 10,000 pounds.
I power back to 42in/2,600rpm and hold 150 knots for best climb speed, winding the VSI to a respectable 3,000fpm (less sparkling than a Mustang, never mind the Yak-3) trimming out rudder as we accelerate and then flipping the cowl-flaps switch to 'close'.
And as my brain catches up with me, once again I'm surprised, indeed amazed, by the smoothness of that big radial engine. For all its eighteen pistons banging furiously away it sounds smoother than a Merlin V12, almost jet-like.
Looking out as I bank towards the Rhine the view is magnificent through the low-silled canopy. I could actually keep it open and rest a nonchalant elbow out, cruising fashion, up to 260 knots, but not today when I feel slightly unnerved by the sheer size of the aircraft in my hands?the lengthy nose, fat with avgas inside the 234 US gallon self-sealing fuel tank housed between the engine and the cockpit firewall, and the down and upward-sloping wings held together at the kink?I can't brush off the fact?by just a set of pins.
I'm beginning to feel I'm in a single-engine bomber, except that the ailerons are surprisingly light and snappy, thanks to their combined spring-trim tabs. Elevators and rudder are heavier but not unduly so. They firm up with increased speed (not so the ailerons) but they too have combined spring-trim tabs to lighten the loads somewhat. For the rest you have the electric trimmers which are very sensitive, similar to an early jet-fighter's.
No time to waste with this fuel guzzler. Level at 6,000 feet and throttling back to 32in/2,300rpm I roll into a set of steep turns left and right, feeling for the buffet. The Corsair turns surprisingly tightly for its mass, and I nibble the buffet at 140 knots while still pulling 3g.
Easing back to 23in, I can hold a 75° bank turn down to 128 knots going right and 125 knots left with plenty of rudder and aileron authority. Rolling out and powering back to 20in, I try a clean stall. The g-break comes at 86 knots indicated with quite strong airframe buffeting. The nose drops straight ahead as I unload and push up to 26in power to recover with just a touch of rudder to keep the ball centred.
Very well-mannered is the Corsair?but let's see now with flaps. At 10° it stalls at 78 knots, again with no rolling tendencies. 20° and its down to 72, with a mild roll to the left; 30° to an astonishing 67 knots with a more marked left wing drop but ailerons still very effective as I waggle them slightly on the recovery.
The 50° full-flap stall is more dramatic, heralded by pretty strong buffeting, stick lightening towards the end of its aft-travel and some degrading of directional control. It finally quits flying at a mind-boggling 65 knots, left wing dropping smartly and with a higher sink-rate, but the recovery is as straightforward, albeit using more rudder to counteract the torque once I've put the nose down and go easy re-applying power. In all we lose about 700 feet.
Enough for today. I'll leave the aeros for the next trip, except perhaps an aileron roll or two on the way back to shape me up for the landing. At 220 knots, nose up 20° over the horizon for good measure before unloading to zero angle of attack, the wings snap into the roll with alacrity and I'm pushed against my lap-straps and suddenly become light-headed as the centrifugal force throws me out for being so high above the fuselage's rolling axis.
So on my second attempt I barrel the manoeuvre ever so slightly, and stay in my seat. As I will later learn the ailerons become increasingly fierce with speed, so effective are the spring-tabs, to the point that by 300 knots you may only use half-stick throw.
Loops, Cubans and barrel rolls are majestic, I will also subsequently discover. The only coffin corner to watch out for is the massive kinetic build-up if you leave the nose below the horizon just a tad too long. A good entry speed for a 4g loop is 270 to 280 knots which will almost every time reward you with the sight of streamers thick as fire-hoses trailing off your wing-tips on the pull-up, and again on the pull-out. You go over the top at around 130 knots with a 2,500 to 3,000 feet height gain.
Tuck the nose over the vertical early, so as to avoid becoming a five-ton missile destined for a fiery hole in the ground, and manage your recovery speed on?or close to?the buffet nibble, as needs be, and you will level out with a few hundred feet to spare.
But back to the present and it's time to go home. I call Bremgarten inbound while ten miles north. Then, ascertaining that the circuit is clear, I head south along the Rhine to come round for a run-and-break for Runway 05 at 220 knots.
I break hard at the upwind end, throttle back and lower 20° flaps to assist high alpha in slowing us down. Rolling out on downwind I lower the undercarriage at 160 knots, re-trimming, and switch the cowl-flaps over to Automatic. Quick pre-landing checks done and already abeam the threshold I tip in for a curving approach for better visibility past the nose, moving the propeller to fine pitch and checking hydraulic pressure stands at a healthy 1,500psi.
Rolling out on a shortish final I ease power back a bit to establish 100 knots as Achim recommended. It feels too fast the moment I've lowered full flap, so I ease a bit further to ninety, trimming back. The approach is nice and stable, offering me a good sight of the runway as I break the glide with 85 knots crossing the threshold. Can it be this easy, I wonder?
Early-model Corsairs were notorious for their 'springy' undercarriage which caused the aeroplane to skip over the deck wires, but in this last-of-the line type the problem has long since been remedied, as have a few others. It's the most viceless of the lot. Still, there is the higher roundout to judge so I ease back the power to a trickle, minimising the sink rate.
As the runway skims under me, suddenly the cowl flaps open up ahead signalling ground contact as they only deploy when the leg oleos compress on touchdown. It's been that smooth.
For once I'm not claiming beginner's luck: the Corsair has consistently flattered me on landing for no better reason than it is speed-stable, highly-controllable down to the stall and has the most wonderful long-stroke undercarriage which absorbs and dissipates energy like no other. It just settles on the runway, except of course if you go for a three-point landing into a short field and must then slam it down, carrier style.
But the landing is not over. As I fly the tailwheel down (kept locked since pre-takeoff) the view ahead disappears and I'm back flicking my eyes right and left to stay on course, stick firmly against my belly and playing the rudder while it's effective.
With today's light winds it's no big deal, except for when the rudder loses aerodynamic authority and I have to tap a brake?ever so carefully?to stop the nose swinging round like a big naval gun and taking me for a ride into the weeds. Crosswind landings are more challenging because the wind tends to get under the upwind wing, but a prompt raising of flaps will help matters.
We roll to a stop in about 750m. An experienced pilot can land in much less, but why should I try?
I want this Corsair to go on for years and years, long after my time; to wow appreciative crowds and inspire other boys to dream what once seemed to me the impossible dream, and to continue carrying the torch for those gallant young aviators who flew, fought and often died in such an aeroplane in order to help preserve our freedom.