Flight-Testing the Zero

by C Budd Dugan

Nice to fly but dangerous in combat is test pilot's verdict on a Zero found practically undamaged in Aleutian bog.

You can take it from Lieut Comm Charles "Tommy" Booth that the Japs have a mighty sweet airplane in their Mitsubishi '00 Zero. But this fighter pilot veteran of the African invasion says that he wouldn't swap cockpits with any Jap pilot on any fighting front. "The Zero is a fine flying sportsman's plane," he says, "but as a fighter it's a potential furnace."

Chief of the test section at the Anacostia Naval Air Station in Washington, DC, Commander Booth has been flight-testing a Zero (this model is known as Zeke) ever since the plane was flown from the west coast.

Zeke, born and constructed somewhere in Japan from some Jap and many US and British ideas, joined the Navy some time ago when a Nipponese pilot landed the plane in an Alaskan bog. According to Naval records, the pilot became lost in the dangerous North Pacific fog and when his gas ran low brought the plane down rather than commit suicide.

A hot little airplane with small landing wheels, Zeke couldn't take the rough terrain and flipped over on its back. When the plane was located by Yank sailors they found the Jap hanging by his safety belt, dead. The impact had broken his neck.

A hasty examination revealed that Zeke was a prize package. With the exception of landing gear, tail and engine cowl damage, the Zero was almost perfect. Unexplained were two .30-caliber machine gun or rifle bullet holes in the fuselage and motor cowl. Neither of the bullets hit a vital part or did sufficient damage to make the plane unflyable. One had nicked a piece out of one of the engine's cylinders and the other bored two little vents in the fuselage.

Zeke, the first Zero taken in such fine condition, was righted, given emergency repairs and flown south to the San Diego Naval Air Station by a Naval pilot. At San Diego, Zeke was gone over carefully by experts, the damage was repaired as well as possible and Zeke was ready for flight testing.

Naval flyers squeezed into the pint-sized cockpit designed for the short-legged Jap pilots and began flying the plane. But there was a feeling that the Zero wasn't putting up the maximum performance possible for the Jap's top fighter. More adjustments had to be made since it seemed that the crackup in Alaska had caused internal injuries that were impairing flight performance.

It was decided to ship Zeke to Anacostia (near Washington, DC) where officers of the test section there could learn the faults and virtues of the Zero. At first it was planned to freight the plane east but with the engineer's report that Zeke's wings were not detachable it was thought best that it be flown.

Strangely, not a single official or unofficial airplane spotter reported a Zero flying overhead during the entire coast-to-coast flight. Perhaps the reason was that when the plane was flying low the spotters could recognize the Naval insignia and paint job that Zeke had been given at San Diego.

Recently returned from action in Africa where he was decorated with the Navy Cross for leading a Grumman Wildcat squadron on strafing missions during the landing operations, Commander Booth was assigned to test-fly Zeke. It was his job to learn everything possible about the ship's flight characteristics and meanwhile adjust the airplane to give maximum performance.

Almost daily for several months he tucked himself into Zeke's cockpit. He climbed the little ship to learn its critical altitude. He checked the report that came east with Zeke that Zeros develop a tail flutter when diving in excess of 380 mph.

After each flight Commander Booth would make suggestions to the ground crew for improvements and adjustments. Soon Zeke was clipping along at what is believed its maximum speed of 328 mph and climbing at 2,600 feet per minute.

"I find Zeke … as maneuverable as a trainer at speeds around 200 mph," said Commander Booth, "but it gets darned hard to handle when you open up the engine…. At high speeds the Zero is heavy on the ailerons."

He is convinced that the Zero has nothing on any US fighting airplane. While Zeke is highly maneuverable it isn't any more so than our own fighter planes. It is slower than our planes and has two faults that make it a death trap.

"I like to fly the Zero," said Commander Booth, "but it is a dangerous plane in combat when compared with our aircraft…. There is absolutely no protection for the pilot in armor or bullet-proof glass, and every gas line and tank is just inviting a bullet. The pilot sits with his feet practically parked on the fuselage tank. In the wings on either side of his feet, is a group of fuel tanks. They hold 100 octane gasoline. They are the reason for Zeros exploding in mid-air…. When you down a Zero you are almost sure of getting the pilot … the guy hasn't a chance."

The armament has been removed from the Zero but Commander Booth said standard equipment calls for two 20-mm cannon and two 7.7-mm machine guns. The plane is also equipped to carry a load of bombs or a droppable gas tank.

Fully loaded, except for bombs or the extra gas tanks, Zeke weighs 5,555 pounds. Stripped, its weight is around 3,781 pounds. According to the tape line Zeke is 30 ft 3 in long and has a span of 39 ft 5 in.

The Japs use no more metal building their Zeros than absolutely necessary With the exception of the fabric-covered tail and ailerons, construction is of a good type of aluminum alloy. There are some evidences of spot welding, although most of the airplane is flush-riveted.

An indication of extreme conservation of metal is evidenced in many small pieces of wood. The handle used to raise and lower the seat is tubular steel or aluminum but topped with a little wooden plug. Handles for snaps, minor controls and brackets are beefed-up with wood in the same way a kitchen knife has a handle made from riveting two pieces of wood together.

Zeke is a creature of gadgets. Commander Booth says, "the Japs must have midgets to take care of the ground crew work. While the construction is simple basically it is almost impossible to reach many of the tiny parts and pieces strewn throughout the cockpit, fuselage and wings."

The Nipponese intended to provide their pilots with parachutes if Zeke's seat is an indication. It is quite similar to the bucket-type seats on Allied aircraft which are designed to hold a seat-pack parachute. Once the seat almost got Commander Booth into trouble. When he was coming in for a landing at Anacostia, one of the bolts fastening the seat to the fuselage gave way and dropped the 5 ft 10 in Naval officer to the floorboards. Fortunately, when the seat gave way he had his wheels down on the runway and was able to stop safely.

Tiny Nip pilots might be comfortable in the pint-sized cockpit but it is agony to a full-sized American to wind his legs around the control stick and down under the dash to the small rudder pedals.

In the early stages of the war many stories were going the rounds that the Japs were flying with virtually no instruments. This is far from the truth. The Jap pilot has as many instruments in his cockpit as do our pilots — perhaps more. And, since they are practically exact copies, they are just as good.

Much of the radio equipment found on Zeke was built by, or is an exact copy of installations manufactured by Fairchild. The Fairchild trade-mark is still to be seen on the plane's radio compass. Other instruments are similar to American products and are accurate and well-constructed.

Except for a very few flight-test instruments and an air speed indicator, Commander Booth is using the original flight and engine instruments. "The only reason we installed the American air speed indicator," he explained, "was because we wanted to make sure it was accurate…."

Seated inside the cockpit, Zeke appears as jumbled as a 5 and 10 cent store counter. The panel is a maze of instrumentation. On the left is a combination throttle, gun selector switch and firing handle. In combat the Jap pilot flies with his right hand on the stick and his left on the throttle and gun controls. His thumb controls the cannon and machine gun selection. To fire he squeezes the trigger with four fingers. The trigger is unlike the conventional British and American electric button and has a squeeze arrangement similar to that of the old-fashioned auto emergency brake.

Directly behind the throttle control is the bomb release switch and behind that the radio. Two lights, about the size of a bicycle head-lamp, mounted on the left and right of the pilot, provide cockpit light.

Practically every instrument, button and gadget on the plane has been relabeled in English. While the original air speed indicator was calibrated in knots similar to those used on US Navy craft, most other instruments have their names and uses in Nipponese characters. Numbers and positions, however, are mostly in Roman numerals.

Clambering out of the cockpit, you notice more gadgets. Push-buttons pop in and out leading to the cockpit. A combination push-button thumb screw opens the gasoline tank hatches for fueling. Other push-buttons open and close sections used while servicing the guns and engines.

Deep in the engine cowl you can see the nick caused by the .30-caliber bullet in one of the cooling fins of a bottom cylinder. Commander Booth explains that the engine is 950 hp — a combination of two well-known American air-cooled engines. The power in its 14 cylinders is stepped up by a single-stage supercharger. The propeller and propeller pitch controlling gear is a direct copy of a well-known American propeller.

Commander Booth is not sure if the propeller unit is still out of line from the Alaskan crash or if it is typical of all Zero propellers for this is one place where the Jap copying slipped up. Supposedly a constant-speed propeller, US flyers handling Zeke have reported they have a difficult problem keeping the engine turning over evenly.

To give the Zero its six-hour range, 140 gallons of gas are carried in the plane's regular tanks and 87 more are carried in a droppable tank mounted between the wheels. The engine burns only 37-5/6 gallons of gas per hour while cruising.

The landing gear is finely designed and offers little wind resistance when retracted. Covering on the outer side of the landing gear leg fully covers the gear when retracted except for the lower section of the tire. This is covered by a hinged flap mounted in the underside of the wing. The wheels retract inward towards the fuselage. Tires, now replaced by a US make, are high pressure.

Zeke was either carrier-based or intended for service on a carrier as the landing hook is in place. The rear wheel is hard rubber of a style discarded several years ago by our Navy and is fully retractable. An hydraulic system operates the retracting gear for all wheels. The brakes are operated by pressing forward on the rudder pedals.

The wings illustrate the typically close and minute work which goes into the Zero. In some places the pieces are very tiny and studded with rivets. The hatches for the Swiss-designed Oerlikon cannon are set flush, but are easily accessible. Each cannon holds 60 rounds.

While designed for carrier operation, only two and a half feet of the wing fold back for storage in the carrier's hangar. The tips fold manually after several buttons are pushed and a lever is pulled.

The flaps are large and mounted conventionally from the fuselage outward for one-third the span of each wing. Ailerons are also very long, running from the end of the flaps to the edge of the retractable tip.

There is no external bracing either on the tail or low-mounted wings. The tail is clean, smooth and elliptical. A tail light, enclosed in a clear plastic case, forms the tip of the sharp fuselage end.

According to Commander Booth, Zeke was constructed in February, 1942, and had flown but few hours when it was taken by the US Navy. The manufacturing data was found painted on the left rear side of the fuselage just forward of the tail unit. While the characters which give the manufacturer's name and other details of the plane are in Japanese, the date of construction is in Roman numerals.

Zeke's career in the Navy is almost over. It has already given the Allies many interesting performance figures. It has been stunted, dived and twisted as it was put through every test known to flight engineers. Now Zeke will join the Army.

Zeke was scheduled to undergo stress tests at Wright Field and to be tom apart so that engineers can learn still more secrets of the "potential furnace" that the Japs call a fighter.

This article was originally printed in the December, 1943, issue of Flying magazine, vol 33, no 6, pp 65-66, 138.
The original article includes 4 photos of Zeke, 2 in Japanese markings and 2 in American markings.
Photos are not credited.