(Continuing from my Part I) Capt. Gordon Vette knew that if they did not try and help, Prochnow's chance of survival was minimal. In the search attempt, Gordon Vette utilized the (so-called) "Aural Boxing" (search) technique (one that's commonly described in the SAR textbooks, but, personally, had intrigued me, in the story), so, here, I've wished to mimic it, myself, albeit, in an (overly simplified) manner (see below). Vette recognized that the VHF communication link could be exploited to locate the Cessna. He requested that the Cessna orbit continuously, while Prochnow would be talking non-stop over the radio, as Vette raced through the VHF range circle which had a radius of about 200 nm. 

My simulated radio-source (the Pago Pago (TUT) VOR) had a Service Range, I found, of about ~195 nms, at a flight altitude of 33,000 ft (same altitude as that of the RW DC-10). Please refer to my (SimBrief) Screenshot (the very last image of the set, below), with American Samoa's capital, Pago Pago, shown in the center of the MAP. So, for my purpose, here, without a (RW) VHF Radio signal from a real Cessna (or Emergency Locator Transmitter (ELT)), I've used the Pago Pago VORTAC (TUT) of frequency 112.50 MHz, as the source of my (simulated) ELT signal and tuned both my (DC-10) NAV Radios to it. Then, I've enabled the Morse Code Identifiers for both NAV1/NAV2 Radios of my DC-10 (see shot of the pedestal Radio Bay, below), thereby continuously listening to the audibles, and also monitoring the DME of this VOR source (please see the Dual RMI gauge in the cockpit shots). This DC-10 (SIM)'s [VC] HSI, located to the right of the DRMI, also shows DME at top LHS of the gauge.

Referencing the "Aural Boxing" pattern Screenshot (the very last image, below), I've flown the DC-10, at 33,000 ft, sequentially as follows, assuming, for simplicity, to start with, the location of my (simulated) ELT somewhere in the front and to the left of my DC-10 flight path:

1. I've flown from [1] where I first heard the IDENT till [2] where I lost the IDENT, noting the LATLONG positions of [1] and [2] from my INS CDU, thus giving me the first Chord (colored Red) within my VOR range (yellow) circle.
2. I've then reversed direction flying from [2] to [3], turned 90 degrees left towards [4] till I lost the IDENT, again reversed direction and flown to [5] where I lost the IDENT, thus giving me the 2nd Chord (colored Blue).

My custom INS (set to POS display) on the DC-10 (SIM) provided me the exact positions (LAT/LONG) of the points ([1]/ [2]/ [4]/ [5]), which are also noted/plotted on the (SimBrief) Screenshot. Per Aural Boxing rule, the two (mid-point) perpendiculars, shown as green lines, off my Red and Blue Chords, would intersect at the location of the ELT. It was indeed gratifying to observe my intersection point [6] just above Pago Pago, as it should be... (So, Aural Boxing was validated in my simple experiment with this DC-10...). In the Final step, I've tracked from [5] to [6] while continuously descending from 33,000 ft (and gradually slowing down from Mach 0.82 / Airspeed 300 / Groundspeed 500) ...towards the ELT of the Lost Cessna....🙂...here the TUT VOR....just as Rain has picked up and darkness has fallen.... (See images below) ...

In the RW event, enormously more challenging than my flimsy experiment here, Capt. Vette acquired VHF contact from the Cessna at one point and lost VHF contact at another point, at which time he would turn his DC-10 by 90 degrees left and continue his aural box pattern. Using appropriate extrapolations of his flown segments within the VHF range circle, the crew established the center and the location of the Cessna. Unfortunately, the Cessna, still, could not be found by sight. As the light conditions worsened, Prochnow considered ditching in the ocean (which would make finding and survival near impossible), but Vette continued to encourage him not to give up. Prochnow soon saw a light on the water’s surface, which was actually from an oil rig (see symbolic screenshot, below, of an oil rig, shown off the NZ coast near Auckland) under tow whose coordinates (31°S, 170° 21’E) were relayed to the DC-10 and, thereby, enabled a rendezvous with the Cessna. This oil rig happened to be (fortuitously) towed from New Zealand to Singapore, at the very same time...! The Cessna was (conclusively) determined to be less than 150 nm from Norfolk and was given a steering direction by Vette of 294° magnetic heading to Norfolk Island (see MAP). Prochnow was able to make it to Norfolk Island with his remaining fuel after being airborne 23 hours and 5 minutes arriving close to midnight 8 hours beyond its ETA (see, below, Cessna arrival shots at Norfolk). The DC-10 continued on to Auckland where it arrived safely (see, below, DC-10 arrival shots at Auckland) a few hours later than its scheduled arrival time.

McDonnell Douglas company awarded the Flight 103 crew a certificate of commendation for "the highest standards of compassion, judgment and airmanship", and in 1980, the Guild of Air Pilots and Air Navigators also awarded Vette the Johnston Memorial Trophy for outstanding air navigation in recognition of his performance in the rescue.

Hope you enjoy this story and the pictures of my DC-10, below, replicated as a (feeble) reminder of that remarkable (RW) rescue effort...! If you wish, search for "Jay Prochnow images" and you'll see pictures of both the (RW) heroes of the event...! You may also wish to see the movie if you've not already. I highly recommend it...it's quite tense and gripping at times... (Note: BTW, in the movie, you'll notice that the plane is a twin-engined B767-200, not a trijet DC-10...) ...

Thanks for your interest...!

Another fine set of shots, thanks for showing !

cheers 😉

 Good looking shots and more great story line . 

Very nice shots again! 😉 

That was outstanding!  Much appreciated.

Friends: Thank you for the kind comments...it was a good bit of learning on my side too...🙂...!

Something about listening to those repetitive melancholy beats of the NAV Morse Code audios in the dark always gets to me...someone is calling me...non-pilot speaking here....🙂...it felt strange here listening intently to the Pago Pago VOR signal from 33,000 ft, and especially when it would suddenly go silent at the either end of my above Aural Boxing Chord segments...suggesting that I reverse direction...

In the RW, I read that, throughout the procedure, the observer (e.g., Vette here) must not adjust the receiver volume. A constant volume helps assure that "signal heard" and "signal fade" positions will remain consistent...so Vette could turn the (massive) DC-10 by precisely 90 degrees at the right spot.... to start the new sequence...

 

 

Most interesting story line, P_7878!! I very much remember that movie. Maybe i can find it again on YT

On 10/21/2022 at 4:14 AM, bernd1151 said:

Most interesting story line, P_7878!! I very much remember that movie. Maybe i can find it again on YT

Thank you, bernd, yes, you can find it in YT, though, I think, the formatting for viewing may be limited...Cheers ...!!