Disaster due to unwitting lift-off
Flying-boat was to be tested on water, not in the air
It was a flight that was never supposed to happen — and two people were killed. On a summer’s evening at Auckland’s Milford beach, onlookers were horrified to see a three-seater flying-boat lose speed, turn to the right, spiral downwards and crash into the sea.
The new and unlicensed seaplane’s two occupants, Captain Donald Harkness, 34, and mechanic Charles Field, 38, drowned. Harkness, an experienced pilot and war hero, hadn’t flown the recently assembled seaplane before.
In World War I, he was awarded the Distinguished Service Cross for a daring bombing raid near Brussels which set a massive German Zeppelin airship shed on fire.
There was evidence at an inquiry into the flight to the North Shore that the take-off was unintentional; Harkness only planned taxiing tests on Waitemata¯ Harbour.
Witnesses heard explosions like engine backfires as the small plane plummeted about 5.30pm on Thursday, December 12, 1929, several hundred metres from shore. A man on the beach with binoculars saw a hand reach up from within the floating wreckage.
“The effort was apparently fruitless,” the Herald reported, “for, although he tried for several moments to extricate himself, he sank back and disappeared as the hull subsided.”
People rowed out in small boats and two life-saving team members swam out and dived under the wreck, trying, unsuccessfully, to release the one man they could see.
Once it was clear the occupant or occupants couldn’t be released, a lifesaving line was attached to the tail in a failed attempt to tow the sinking machine to shore.
The same evening, an Auckland Harbour Board launch towed it to near shore, from where it was hauled by rope on to the beach.
The nose of the metal-hull machine had been pushed back on to the open-top cockpit, locking the two men in place. A 23kg boulder was wedged between them.
The single-engine Dornier Libelle flying-boat, assembled in Auckland, was built to carry a pilot and two passengers. It was destined for air taxi work for Aerial Services, registered shortly before the crash by Harkness family members and others.
In pre-licensing tests, some instruments didn’t work properly, there was a collision with a moored boat, and the engine had difficulty spinning fast enough because of petrol pump issues.
The plane couldn’t carry a full load and an auxiliary petrol system was installed.
Captain W. Mann, who took the plane on test flights, said it was airworthy when he flew it the day before the fatal crash, but had never run at full efficiency.
“Captain Harkness was a very level-headed man, fully appreciating that a flying-boat required different handling from that of an aeroplane, and I am convinced that he had no intention of flying when he took the machine out on Thursday.”
Mann surmised that stones were used to provide ballast for taxiing tests. The engine spun faster than expected and the plane lifted off.
Mann thought it might have become tail-heavy with a failing engine, so to increase engine speed Harkness might have switched from one petrol system to the other.
“While the mechanic was trying to throw out the stone the machine may have stalled and gone into a spin.”