SIT UP AND PAY ATTENTION!(anyone interested in learning something moderately
useful about the "Cooper" hijacking case)
HOMINID, SET UP AND PAY ATTENTION FOR A MINUTE HERE!
ARINC had EVERYTHING to do with those teletype messages and the networks over which they were transmitted. ARINC stands for AERONAUTICAL RADIO, INCORPORATED. It was set up to provide radio communications for the airlines that was not related to air traffic control. If you don't know what ARINC does, then Goggle it! The VHF radio frequency being used for the phone patch was an ARINC frequency and, again, the ARINC teletype messages were prepared from voice messages over that frequency.
Thank you for the condescending, basic (but useless) information. Someone who doesn't know could indeed easily find out by a web search something about "what ARINC
does." (I don't recommend Goggle.) Someone who wants to know something actually
relevant to the cooper case will have to find out what ARINC
DID IN 1971 and what part of that service was actually
USED BY NORTHWEST AIRLINES IN 1971. Your last sentence above is totally wrong, as I'll explain presently.
Someone who learns more than what your simpleton "Goggle" search yielded can find out that ARINC was indeed set up to provide radio comms for the airlines. However, it was "set up"
by a group of airlines and was originally owned by that group. When that group "set up" ARINC, they transferred their existing long-range radio comm network assets to this new corporation they had established. Those airlines did it voluntarily. Not all airlines participated. NWA was
not part of that group of airlines that transferred their comm networks to ARINC.
In 1971,
Northwest Airlines had little need for ARINC and
used ARINC very little. The reason for this is simple.
Northwest Airlines had their own very extensive, very capable long range radio communications network. Every time they extended their service area, since the beginnings of the airline, they would install a very good radio station at each new airport they served. Had they ever sold off their radio network as a separate company, that company alone would have been worth probably 5%-10% as much as NWA. NWA had its own frequency assignments from the federal government.
(I was amazed when I learned how recently NWA finally transferred its long range radio communication assets to ARINC. It was just a handful of years before their merger into Delta. 2004 if I remember right.)
Because NWA had its own very good comm network in 1971, NWA's routine use of ARINC was pretty much limited to occasional situations in which a flight found itself somewhere in which it could not "get through" by radio but needed to communicate right away (rather than waiting until they could get through). The flight crews trained for this even if they never ended up actually having to do it.
To use ARINC in this situation, the company had to have an account with ARINC. The flight crew would radio the regional office of ARINC using the frequency everyone knew for that office. They would identify themselves (e.g., "Northwest flight 305") and say they wanted a message relayed to company dispatch, flight ops or whatever (as identified in the account subscription).
The ARINC office would take the message by voice, write it out in a highly structured way using standardized abbreviations, QA it, then teletype it to whatever airline office was identified in the airline subscription. ARINC used people very familiar with airline lingo to do all this, so
the teletypes they sent out did not have the bonehead mistakes apparent throughout the teletype messages we see in the "transcripts."For those situations in which a flight was "out of contact," NWA could also call ARINC to have ARINC contact the flight and relay a message to the flight. And, they could arrange for ARINC to set up a "phone patch."
"Phone patch" was an ARINC service that NWA actually did use during the hijacking, but not at all as you claim.
ARINC had a lot of radio stations scattered around, like at Salem, Eugene and Medford, OR. They also had a lot of radio frequencies assigned to them. (The same was true of NWA.) These assets were constantly being used for airline comms wherever the flights happened to be. But, in any specific area, ARINC generally had some frequencies available that were not being used.
When ARINC received a call from NWA (for example) to set up a "phone patch" with a flight, ARINC would select one of its frequencies that was not being used in the area where the flight was (or was going to be) and would tell the airline to use that selected frequency. ARINC would connect a telephone circuit to a transceiver set to the selected frequency. The other end of the telephone circuit would be at an NWA office.
The flight 305 crew would talk into their radio (set to the assigned frequency), the transceiver nearby (like at Eugene) would receive the signal and send it out over the telephone circuit. NWA flight ops would talk back into the telephone, the signal would travel by telephone to that transceiver, which would convert it to a radio signal that would "wing its way" up to flight 305. A
patch between radio and telephone, hence "phone patch." No teletype. However, this ARINC service did normally include the recording of all communication on the circuit.
When the flight eventually flew long enough to get close to the range limit of that initial radio station and its transceiver, ARINC would have to arrange to provide similar service through another radio station (at Medford, for example). Another frequency would be available there, so ARINC would set a transceiver there to a new frequency and would patch that transceiver output into the same telephone circuit. And ARINC would notify NWA, which would notify the flight.
Anyone with the right radio could listen to the communications. But no flight other than 305 is going to talk on the frequency because doing so could result in ARINC terminating service for their airline. Besides, all the airlines have a stake in being able to have such semi-dedicated service. The phone patch was similar in function to a "dedicated" telephone line.
Back to the "phone patch" and hijack night:
When NWA found that 305 was going to be flying south of Portland, they knew they needed to arrange for comm coverage south of Portland. This is because their own network didn't extend down there, because they had no routes down there. So, they contacted ARINC and arranged for the phone patch south of Portland. The patch was set up and 305 actually switched over to it even before reaching Portland. Curious, isn't it, that the first use of the phone patch started when the teletype messages ended?
As the flight proceeded to Reno, ARINC assigned new frequencies (for different physical areas). The logs and transcripts refer to this. They were the frequency changes that were not associated with handoffs between controllers. At the end, there was even chatter about ARINC needing a bit of advance notice if the flight proceeded on down to Mexico.
The logs in the "Harrison" papers also include references to communications in which someone inquired about whether or not these (phone patch) comms were being recorded, with someone answering "affirmative."
At the bottom end of the transcripts are those for which the only times given are approximate times at the beginnings and ends of recordings.
In between, are the Oakland center transcripts and the teletype messages, which have nothing to do with ARINC as Robert claims. With the teletype messages you have to account for the fact that everything in a message was voice over a radio before the minute after the specified minute. That is, a message identified as 0411 was sent between 8:11:00 and 8:12:00 pst.
Your first sentence above is not clear. Some of the teletypewriter printouts have the times listed both in PST and in Zulu time. The PST is plainly labeled and the Zulu time is in the last line of the printout and is bracketed by two letters on each end. Zulu time is 8 hours AHEAD of PST. There is nothing complicated about this.
Robert99
What I was trying for in that first sentence is that some of the transcripts are at the bottom of the spectrum as far as time precision is concerned. Nothing to do with the teletype printouts.
Your assumption that the voice message was received only a minute before the message was transmitted by teletype is not supported by facts. For a very short message consisting of only a few words, it may be able to format it and transmit it in the same minute that is showing on the clock. But for longer messages, a short paragraph or so and shown in some of the printouts, it may well take two or three minutes for receipt, processing, and transmitting.
Your assumption that there was any "format it and transmit it" is not supported by facts. The messages were
sent in the minute range identified at the end of the message, regardless of when the beginning of the message was first heard.
