Starting big radial engines that have cold soaked can be a real test of skill and to some degree, a bit of luck as well. You definitely want to use a ground power cart for it can be very nasty if the battery runs down just when you get a little exhaust stack fire going. The throttles are carefully cracked open about 1/4 inch. After getting clearance and making sure a fireguard is set, the starter is engaged and the engine reluctantly starts to turn. In very cold weather the engine primer switch is toggled to get some fuel into the blower and the fireguard with the big CO2 bottle gets nervous as the gasoline spouts out to puddle on the ground. We counted the blades of the propeller as they turned. By the count of "nine blades" the ignition switch (mag switch) was turned to BOTH. You used another finger to toggle the induction vibrator switch to stimulate the magneto to throw a few sparks. More prime (raw 100 octane into the engine blower) was added and if all went well, the engine would cough, jump in it mounts, belch smoke, kick, (here you add more primer liberally or it might backfire), and then it would take off at which point the mixture lever was deftly brought up from "idle cutoff" to "auto rich." The starter, primer, and induction vibrator switches were released and everyone looked proud--if it started.
Sometimes it did not start. Repeated attempts led to induction vibrator and starter changes. The worst case though was "icing the plugs." An engine suffering from iced plugs would never start, at least not until summer because each spark plug had a neat little dome of black ice across the electrodes. The ice was the product of the combustion process where the water from the fuel burning collected on the cold spark plug electrodes. It was usually induced by moving the throttles just as the engine fired up.
Over at the old Quonset hut terminal at Idlewild, Trans Carib's DC-4 did indeed suffer from iced plugs on its outboard engines that cold and grim night at IDL. The flight crew was fooled by the ease of the inboards cranking up easily. Back at the hangar we received a call saying they were bringing the aircraft over to our ramp. We couldn't put the airplane in the barn as we had filled it, but we could fire up our two Herman Nelson heaters.
The old Herman Nelson heaters were finicky machines as I have mentioned before. On this night they started easily for they were in regular use and were in the hangar and nice and warm. N-416 appeared at our ramp, inboard engines running, and taxied in. We waved it into the designated parking spot and realized the plane was fully loaded with Puerto Rican families trying to get home for the holidays. In the silence after the two inboards were shut down, you could hear babies crying and a dog barking. We quickly put ground power on the airplane but had no ground heater for the cabin. The plan was to heat the thoroughly iced outboard engines with the two available Herman Nelsons. We covered the outboard engines with tarps and applied the heat through the front to warm the cylinders, melt the ice from the spark plugs, and hopefully, dry them too.
I stood on an Aerostand directing the air into the #1 engine. The tarp around the engine billowed in the blasts of near arctic air. The temperature was in the low single numbers and the wind was howling and the whole airplane shook. The cockpit heater was running but, as you will recall, the main cabin heater could not run on the ground. The cockpit heater was far too small to do any good. We poured the heat to the engines. It was so cold my eyes were streaming and my glasses were frosting over. I opened the tarpaulin a little to leak some heat on me. I looked at the airplane through eyes filled with tears from the cold. The round cabin windows were filled with faces staring out as us wondering what we were doing out there in the cold. I waved at those intense eyes staring at us. The temperature inside the airplane dropped quickly in the wind and cold and shortly, no faces were peering out anymore. The windows had frosted over on the inside.
It was obvious, even out at number one engine and over the chug of the Herman Nelson heater that a furious dispute was going on inside the cabin. Unsurprisingly, these people wanted off this frozen tube. Cleverly though, no boarding stand had been placed up to the airplane so when the cabin door opened the frozen but enraged passengers, by now in full rebellion, could only stand at the threshold and scream at people on the ground.
"Please let us off this plane," they begged. "We are freezing." So was I and I was wearing thermal underwear, two sets of pants, coveralls, a sweater and a parka not to mention wool socks, gloves, a fur-lined parka hood, a wool cap and thermo-pac boots. They were dressed for a flight to the sunny Caribbean.
The Herman Nelsons were in fine form pouring out very hot air and we had been at it for over an hour. Ignoring the pleas of the frantic passengers, the Trans Carib maintenance representative shouted up to me, "That's enough heat. It should be hot enough to start so uncover the engine and we’ll give it a try."
Delays with passengers aboard aircraft are nothing new.
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