Lost in a R4D-8

j1b3h0

Line Up and Wait
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Display name:
Doug
In the summer of 1981, with about 650hrs, I worked as a copilot/mechanic for an outfit in Anchorage, Alaska. Flew a recently surplus Navy C-117 or R4D-8 and a Curtiss C-46. To be fair, I was about 85% mechanic and 15% copilot. Mostly, we flew fish - fresh salmon, from King Salmon to Anchorage, and then shaved ice (with which to pack fish) back to King Salmon.

We once got a charter to fly tons of gold mining equipment from Anchorage to Yakatat, on the southeast coast of AK in the C-117. After fueling, (and oiling) we spent considerable time loading all kinds of odd machines and hardware into the airplane. Given the typical summer Alaska rainy weather, we filed IFR.

My first surprise was when I picked up the clearance: A SID off Anchorage that led us toward Portage glacier, then amber airways to Yakatat. Okay, they mean ADF airways. Really? Well, it just so happened the C-117 had two very swanky ADF recievers on the overhead panel. The 'coffee grinder' type. Old airplanes like the Douglas had big radios in the belly connected to the tuning head in the cockpit. In theory, the pilots would tune the frequency utilizing the BFO: The Beak Frequency Ocillator, while listening to the ADF, one would dial it in 'til the tone (while selected in BFO) was at its lowest frequency, then listen for the NDB identifier, then note or confirm azimuth on the RMI (Radio Magnetic Indicator). I understood the technique, even if I'd never actually done it.

So, we launch and are IMC prior to 1,500ft. The flight goes along fine...until the amber airway part. Whenever I tuned the radio with the BFO and audio ID, we didn't get any azimuth...on either radio. As you might imagine, we were in a non-radar environment. When I found a station with good azimuth, we had no way to identify it. We got hoplessly lost, and eventually turned south over the ocean, and descended until we saw the water, at about 150ft. We were about 10 miles north of Johnstone Island, 40 miles south of Cordova. We landed in Cordova and I then had to hand-pump (from 55gal drums) 450gals of avgas in the 117. Took 35minutes.

Moral of the story: Check Nav radios on the ground.
 
"The Beak Frequency Ocillator"

That's Beat Frequency Oscillator"

I guess I'm showing my age....

I wasn't going to type anything. It's not age, it's interest in accuracy. I knew nothing about ADF five years ago but bought an aircraft with an ADF and a BFO switch position. The ADF is gone now and I don't really miss it...
 
What does the BFO switch do?

Quoting the KR-86 Installation manual, page 3-1:

"In various parts of the world, some radio range stations use an interrupted carrier for identification purposes. A Bet Frequency Oscillator (BFO) is provided to permit these stations to be more easily identified. The function selector switch is simply placed in the BFO position and a 1000HZ tone will be heard while the transmitter carrier is on."

In other words it generates a tone for the Morris Code ID because the ground station only interrupts the carrier for ID. No ID tones are generated by the ground station like VORs do.

The switch positions are ADF, ANT, and BFO. I never noticed much of a difference in function on flights around the mid-west. Then again, I didn't use the ADF much.
 
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