Flight Test : Flying Fortress
Taking the controls of one of the dozen or so Forts still airworthy — a flying tribute to WWII aircrew
A Fort lives in the sky, from three to six miles up, and the only real things up there are the throttles and the feathering buttons, the engine gauges and the rudder pedals, an oxygen mask full of drool, and a relief can half-full of relief.’ B-17 co-pilot Lt Bert Stiles wrote those words seventy years ago in his wonderful book Serenade to the Big Bird ? and as our Fortress rumbled sedately over Florida I couldn’t help but wonder what he’d have thought of our flight. One thing’s for sure ? the skies above Winter Haven are a lot more peaceful than Wilhelmshaven’s.
Serenade is ? in my opinion ? one of the best books to have come out of WWII, while the Flying Fortress has to be one of the most iconic aircraft of all time. Consequently, when the opportunity arose to fly as a B-17 co-pilot I had to think about it for no more than a millisecond, and caught up with the Collings Foundation’s B-17, B-24 and P-51C at Winter Haven in Florida earlier this year. The proud old warbirds looked magnificent in the warm winter sun, and I was practically salivating at the prospect of getting behind the controls. However, before I was even allowed to sit in the Fort, the Foundation’s Chief Pilot Jim Harley put me through a training session ? just as he did when I flew the foundation’s B-24 Liberator. After an exhaustive schooling on the Fort’s systems, services, speeds, and idiosyncrasies ? which took several hours ? Jim and I walked out to the brooding bomber.
Built in 1945 by Douglas, N93012 is currently painted as a particularly celebrated B-17G, Nine-o-Nine. This famous Fortress (nicknamed after the last three digits of its serial number, 42-31909) completed 140 combat missions (an 8th Air Force record), including 126 consecutive missions without a mechanical abort. Its crew chief was even awarded a well-deserved Bronze Star.
N93012 never saw combat, but has survived two major crashes and three atomic bomb blasts! Of the 12,731 B-17s built 8,680 were G models, as are most of the survivors. As Jim and I walk slowly around it, he points out some of the Fort’s notable features, while I can’t help but compare it with its Eighth Air Force contemporary parked nearby. For example, four big, round engines hang from the wings, fitted with the same three-blade Hamilton-Standard Hydromatic props as the B-24. However, I soon realise that there’s a lot more oil on the wings, cowlings and ground.
“Yup,” nods Jim ruefully, “those Wright Cyclones throw out a lot more oil than a Twin Wasp.” Although both types of air-cooled radials produce 1,200hp and feature single-stage engine-driven superchargers and exhaust-driven turbochargers, they are very different in design. Wright opted for a nine-cylinder single-row configuration, while Pratt & Whitney preferred two rows of seven.
Each engine has its own independent fuel system, with a combined capacity of 6,435 litres, although when fitted with ‘Tokyo Tanks’ between the outboard wing ribs and two special ‘long range’ tanks in the bomb-bay this increases to a staggering 13,627 litres! The transfer system pumps fuel at an impressive sixty litres a minute, but only across the wing. An idiosyncrasy that Jim ensures I understand is that in the event of an engine fire or severed fuel line, the fuel shutoff valves are electrically closed by a solenoid. However, if the electrical system fails, the fuel shutoff valves are spring-loaded to open. Thus if you’ve shut down and secured an engine after a fire, it is vital not to turn off the electrics as the fire may restart. This would be a Bad Thing, as along with all that fuel there’s also a lot of oil out there ? 560 litres to be precise. (To put this into perspective, a Cessna 172 carries 212 litres of fuel.)
Although during ground school Jim had said that the turbochargers are inoperative, he still carefully checks the buckets as part of the preflight, before moving on to the ailerons and electrically-actuated split flaps. These are large, fabric covered and take up approximately sixty per cent of the trailing edge.
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The mainwheels partially retract forward into the inboard nacelles, and the tailwheel aft into the fuselage. It is not permitted to cycle the undercarriage more than three times in an hour as the screw jacks get hot, making the extension sequence rather rough and uneven. Braking is by hydraulically-actuated duplex expander-tube brakes; the brake pucks being made from the same ‘Unobtanium’ material as the Liberator’s. The wheels ? and also the flaps ? can be cranked down manually, but in the unlikely event that the wheels just won’t come down, Jim explains that we’ll go and drop the ball turret in a freshwater lake first. Dropping the ball turret is a vital prelude to a belly landing, and instructions and tools are carried in the aircraft. While studying the undercarriage and flaps Jim points out possibly the biggest difference between the two bombers, for although the B-17 is essentially an electric aeroplane (only the brakes and cowl flaps are hydraulic) the B-24 is completely the opposite, with most of its services being hydraulic and only the props, intercoolers and cowl flaps being electric. I wondered if perhaps part of the Fortress’s legendary ability to somehow make it home after sustaining astonishing amounts of combat damage was linked to Boeing’s design philosophy, as hydraulic systems would be much more susceptible to failure.
Stood by the tail guns, the fin, rudder, tailplane and elevator look so big they almost seem slightly out of proportion. Even without flying it, I could see that the B-17 should have good stability in pitch and yaw. All the control surfaces are fabric covered.
As we walk around I notice the multitude of Browning M2 fifty calibre machine-gun barrels protruding from the tail, ball, mid-upper, waist, chin and cheek gun positions. Even though early B-17s weren’t as well armed as the G-model, it’s not hard to see why Seattle Times reporter Richard Williams exclaimed “why – it’s a flying fortress” the first time he saw one. Unfortunately, the machine-gun is not much use against flak, and a particularly sobering statistic is that more than fifty per cent of all the G models built were lost in combat.
Up in the cockpit Jim continues his patient tutorial. The throttles are particularly interesting, as the levers are arranged so that it’s relatively easy to operate them individually, in pairs or all together. The friction lock can also be used to lock all four, or only the inboards. Below the throttles is a useful power chart, with recommended settings for everything from ‘War Emergency Power’ to ? intriguingly ? ‘Hover’. At the base of the pedestal are the propeller levers, while the mixture controls are set in front of the throttles. These work in the opposite way to those in modern aircraft, being pulled back for rich and pushed forward for ICO. To the left of the mixture levers is the rotary knob for the turbochargers, while a panel in front of the levers carries the controls for the hydraulic cowl flaps and switches for most of the electrical services, including the magnetos, flaps, undercarriage and lights.
The pilot has the flight and navigation instruments, while the tachometers and manifold pressure gauges are in front of the co-pilot, along with most of the other engine instruments. The primary power instruments are bordered by a white line, while the fuel pressure dials are delineated in red, and the oil pressure and temperature gauges yellow (standard US Army Air Force colour coding). Cylinder head, carb air and outside air temperature gauges are all in front of the co-pilot. A curious instrument anomaly (and one I’ve never got to the bottom of) is that although America remains firmly wedded to the Fahrenheit system, all of the temperature gauges in this seventy-year old instrument panel (and indeed all the WWII American aircraft I’ve even flown) are in Centigrade.
Jim emphasises that the Fort is a two-crew aeroplane and that I must play my part as the co-pilot properly, as there are some controls that the pilot just can’t reach. I’ll be flying with ‘Mac’ McCauley, who’s hugely experienced in B-17s (over 5,000 hours) and Nine-O-Nine is very much his baby. Now, nobody likes to see their baby mistreated and I soon get the impression that Mac can be quite irascible if things aren’t done to his satisfaction. Indeed, as Jim continues to explain my duties a lot of the briefing contains the phrases “Mac doesn’t like that”, “Mac won’t like that”, and “Mac really doesn’t like that”. I begin to wonder what I’ve let myself in for and ? that night ? spend several hours carefully poring over the checklist…
THERE ISN’T A PRETTIER AIRPLANE IN THE SKY
I meet Mac the following morning, and ? contrary to my expectations ? he appears to be in a perfectly affable mood. As we walk out I remember Bert Stiles’ description of the Fort. He wrote that ‘the Boeing B-17 is a good airplane, whether it’s made by Boeing or Douglas or Vega. It’s a pretty airplane too, in the air. With its wheels down, sitting on the ground, it is a lazy-looking job, with none of the eager look of an A-20 or a B-26. But once a Fort is airborne and the wheels are up, there isn’t a prettier airplane in the sky.’ I wouldn’t say that it’s exactly pretty, but it certainly has plenty of ‘ramp presence’ and I’m thrilled ? and also honoured ? to be its co-pilot.
Once we’re securely strapped in, Mac tells me to fish out the checklist from the pocket underneath my side window. (Incidentally the B-17 was the catalyst for the introduction of the aircraft checklist, as a prototype crashed when the crew neglected to unlock the controls.) Using the challenge-and-response format we work our way carefully through the list, until we’re ready to start. And, just as it would’ve been in 1944, my role today is definitely that of the co-pilot, it being tacitly understood that although I’m welcome to follow through lightly on the controls during takeoff and landing and fly the Fortress in the cruise, whenever the wheels are out of the wells Mac will fly. This is how it was in service (I don’t think Stiles ever logged a landing during his 35 missions) and furthermore Nine-O-Nine is one of only twelve airworthy Fortresses, and Mac’s baby. To be honest, I think that even if I had 500 hours in the BBMF Lancaster, Mac would still do the takeoff and landing on our first flight together.
Having checked that the prop arc of engine number three is clear (this one is always started first as it also powers the hydraulic pump) and that our crew chief is standing by with an extinguisher, I seek out the toggle switches for the fuel boost and pre-oil pumps, starters, primers and ignition boost systems. As all the toggle switches look identical and the ‘Start’ and ‘Ignbst’ ones operate two engines each, it is vital that I get it right. If ? for example ? I pre-oil number one, crank three, prime two and select ‘Ignbst’ for no. 4, I’m fairly sure that Mac’s sunny disposition will not prevail! But Chief Pilot Jim has trained me well, and in no time at all we have the wonderfully liquid rumble of four big, round engines filling the cockpit. I continue my way through the checklist and we’re soon ready to roll.
“Okay Dave,” grunts Mac, “let’s go. Chocks clear?” “Clear my side,” I reply. “Tailwheel unlock, parking brake off” are the next commands?and mis-managing either will incur Mac’s displeasure. The tailwheel lock is operated by a lever set in the floor by the co-pilot’s seat; it allows the tailwheel either to castor fully or be locked in trail. The locking pin is designed to fail in shear, so it is imperative that it is unlocked when making turns. The lock/unlock lever must not be forced, while if the park brake knob is not released carefully its return spring is powerful enough to punch a hole in the sub-panel.
Mac eases the Fort out of its parking space and, as soon as we’re on the taxiway, asks for the tailwheel to be locked. I’m already very impressed by how easily Mac handles this big taildragger. The brakes also seem less ‘grabby’ than the B-24’s (it’s a similar system), although it’s more likely that Mac is more used to them than me. Every time we turn a corner on the way to the runway it’s “Unlock tailwheel” ? “Tailwheel unlocked”, followed by “Lock tailwheel” ? “Tailwheel locked”. Sometimes the lever is quite stiff, but Mac can see when I’m struggling, gives a quick ‘wiggle wiggle’ with the rudder and the locking pin pops out every time. The tailwheel assembly is probably the weakest part of the whole aircraft, and as the locking pin costs $1,000 to replace Mac takes care never to stress it. Indeed, whenever we are on the ground I note that the control yoke is never aft of neutral.
With the run-up and all checks complete Mac carefully lines us up and rolls forward a few metres to ensure the tailwheel is straight. I then lock it; he stands on the brakes and slowly opens the throttles to thirty inches. Even now, with the aptly-named Cyclones blasting four tornadoes of thrust across the tailplane, the yoke is forward of neutral. Brakes off and the Fort accelerates rapidly. Mac sets the throttles to roughly forty inches and then places both hands on the yoke, leaving me to fine-tune the power. I’m a bit slow adjusting number four, and by the time I’ve got all the manifold pressures set at forty inches the tail is up, the airspeed is already past fifty knots and the noise is phenomenal. At about ninety I feel Mac add just a hint of backpressure to the yoke, the eager rumbling of the wheels stops and the Fort sort of waffles into the sky. Everything is very unhurried; it almost feels like an over-sized Cub.
“Positive rate,” I confirm. “Gear up,” replies Mac, deftly stopping the still-spinning wheels. I raise the guard over the surprisingly small switch, click it forward and look out of my side window. The big wheel comes up somewhat ponderously, before half-disappearing into the number three nacelle. “Mine’s up.” “Mine too,” he replies, and a glance at the undercarriage status lights on the panel confirms that the tailwheel is also safely tucked away, so I click the switch back to neutral and lower the guard over it. The speed progressively increases towards the Vy (speed for best rate of climb) of 110kt and Mac smoothly eases the throttles and props back to the METO (Maximum Except Take Off) power setting of 38/23 (38in boost/2,300rpm), makes a further reduction to 35/23 and then to the cruise setting of 27/18. We’ve taken off with the flaps up, so all I have to do is adjust the mixtures, cowl flaps and props. I move each control slowly and deliberately, having identified it first.
We both spot the B-24 at the same time, and Mac is soon easing us into formation. He’s clearly working hard, and our light weight (we’re about two-thirds the weight of a bombed-up B-17) and the fact that we’re flying relatively low and the thermals are starting to pop isn’t helping, although even the bigger thermals probably don’t compare to a near miss from an 88mm flak gun. Mac’s eyes are riveted on the Liberator, so I dutifully scan manifold pressure and rpm, cylinder head and oil temperatures, oil and fuel pressures and the myriad other gauges.
Everything’s perfect, and as we close on the unmistakable shape of the B-24 I sense movement in my peripheral vision and look out of my side window across the tops of two huge prop discs. As briefed, our P-51C escort has joined up on us, and for reasons I can’t fully explain it really looks good to see it there. A Mustang or two must’ve been a wonderful sight to a crew limping home with shut-down engines and wounded men, and I know that photographing the B-17 and its graceful guardian must be an emotional experience for photographer Jim, who is shooting from the Liberator’s starboard waist gun position. His father was a B-17 pilot with the 8th Air Force and even flew on Black Thursday, when almost 25 per cent of the attacking Fortresses were shot down during a catastrophic raid on Schweinfurt. Over a beer that evening he admitted that his Canon’s viewfinder had unaccountably misted up once or twice.
CO-PILOT TAKES HIS TURN
With all the pictures in the can we move out of formation and Mac lets me fly. I try a couple of gentle turns and instantly realise it is important to lead with the rudder and that the controls are quite heavy and also not very powerful, although this may be because they’re all fabric covered. It is certainly a much nicer flying aircraft than the Liberator. The handling somehow seems more positive, albeit rather ponderous. It also seems very stable ? in fact it really does feel like a giant Cub. Nevertheless it must’ve been very hard work to fly a heavily-laden B-17 in close formation at high altitude, through a ‘diseased sky, blotchy with ugly bursts of flak’. Cruising through Florida’s peaceful sky with that iconic yoke in one hand and the other resting on the throttles with the massive motors lazily loafing along at 27 inches and 1,800rpm is an almost surreal experience. It’s also seventy years and thousands of miles from Nazi Germany, and the ‘black flak and nightmare fighters’ described in Randell Jarrell’s powerful poem ‘The Death of the Ball Turret Gunner’.
Mac indicates that we’re fast approaching Zephyr Hills and resumes control while I retrieve the checklist and check booster pumps and cowl flaps, set the mixtures to ‘auto-rich’ and lower the flaps to fifteen degrees. As we turn downwind I increase the rpm to 2,100 before lowering and visually checking the undercarriage. On final Mac calls for full flap, then greases Nine-O-Nine on in a perfect wheeler and tells me to bring the props slowly up to max rpm before he gently lowers the tail.
DRAWS A LARGE CROWD
As we taxi in I can see there’s a large crowd waiting for us, for the superb spectacle of these magnificent machines roaring through the overhead has drawn a large crowd, all eager to see some living history. The B-17 will visit over a hundred American cities during the Collings Foundation’s 2014 ‘Wings of Freedom’ tour, and be seen by hundreds of thousands of people. Would this many people go to see some dusty, lifeless aircraft in a museum? I very much doubt it.
Once we’re safely chocked I regretfully ease the mixture levers forward into ICO, and as the muted thunder of our mighty engines dies away and the giant propellers slow to a stop the sudden silence is profound. As I sit there listening to the whirling diminuendo of the gyros as they spin to a stop, I am filled with a sense of enormous respect for the crews of the ‘Mighty Eighth’. I may have just flown a Fortress, but I simply can’t comprehend just how terrible it must’ve been fighting and dying at 30,000 feet. To be sat in the seat I’m sitting in, simultaneously soaked in sweat and suffering from frostbite, while watching a good friend’s aircraft vanish into a fireball, or counting the parachutes as a crew tumble from a stricken bomber. One week, Stiles flew four missions in five days, and wrote that ‘it’s always work, and nine hours of it on a Berlin trip knocks you flat, and if you have to drag out of the sack at two in the morning for another nine hours of the same thing, you feel like going over the hill with no forwarding address.’ And brave men like him didn’t just do it once, but over and over again until fate claimed them or ? for the lucky ones ? their job was done.