Tony747-400

Interesting Read On ETOPS

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Very nice! Learning ETOPS was my favorite part of training and definitely the most useful and organized tool. If all long-haul simmers could take the time to learn and plan according to these rules, there is no such thing as a "boring flight!"

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If people read about Minimum Navigation Performance Specification they would realise the vatsim transatlantic procedure is complete crapolo there is no one controlling traffic at 30 west and there certainly isn't a floating hf and vhf transmitter bobbing around the north atlantic.

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19 minutes ago, tooting said:

If people read about Minimum Navigation Performance Specification they would realise the vatsim transatlantic procedure is complete crapolo there is no one controlling traffic at 30 west and there certainly isn't a floating hf and vhf transmitter bobbing around the north atlantic.

Pete, you've said this before and it's still nonsense now.

Apart from using VHF frequencies (purely because MSFS does not support HF radios), everything else on VATSIM is basically in line with how things work over the Atlantic. CPDLC is cutting down the number of voice transmissions somewhat, but I can assure you there are still a contingent of radio operators at Ballygireen.

If you don't believe me, take it from NATS themselves:

 

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I'm well aware of CPDLC. but the idea of you chatting away on your headset clear as day at 30w very clearly on a frequency to a guy in Shannon isn't realistic. Sure you can get CPDLC messages,  handoffs the whole procedure but  what what we are doing is wrong. 

You then have  have  people on incorrect tracks at the wrong tracks times going the wrong way at the wrong levels at the wrong speed  but thats for a another day 

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5 minutes ago, tooting said:

but the idea of you chatting away at 30w very clearly on a frequency to a guy in Shannon isn't realistic

As a communications engineer experienced in HF radio, I can assure you this is routine stuff.  Our USAF aeronautical station was at RAF Croughton, NE of Oxford, and from there we could talk to aircraft anyplace in the N Atlantic including AF One (at the time, before satellite). Why do you doubt that?

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air-to-ground-datalink-communication-7-6

 I know you can talk to aircrews at 30 west using satellite, or using relay etc etc.   Last night at work one of our 747s had a windsceen wiper come out of clip / housing and nearly broke off and was flapping all over the place. they  nearly diverted to Shannon as the skipper was panicking. We spoke to them for 30 mins clear as day from our ops room in London but that was using satellite not vhf 131.700 (when they where quite far south in the Atlantic as they where last night as it happened at 0400am!!) you would of never of got them on 131.700 or whatever vhf they use on vatsim.

In the end he carried on as it was the pnf side and not the pf side. 

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43 minutes ago, tooting said:

You then have  have  people on incorrect tracks at the wrong tracks times going the wrong way at the wrong levels at the wrong speed  but thats for a another day 

Obviously you have to leave some real world restrictions and procedures at bay to accommodate for a virtual environment that is 24/7. Not everyone has the ability to fly at the time when tracks would be active. 

 

Also This - "FAA licensed dispatcher B744-400 + 747-800" This is triggering me to no end... :P

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I did my dispatchers licence in Florida 10 years ago the  company I worked for back then paid for it.  Compete waste of money as it's not needed In the UK but looks good on a CV,  the company I work for now has 744s and 748s

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Pete,

That is a lovely VHF coverage map and clearly VHF is line-of-sight. This is not the case for HF, which reflects off the ionosphere and can therefore be received 'over the horizon', hence why it is used for long-range communications such as over the Atlantic and Pacific (Dan I'm sure would be able to give a better explanation than I!).

Crews certainly do talk to Ballygireen and/or Gander, on voice, at 30W, routinely. There is less voice position reporting now because of ADS-B and CPDLC, but it still happens and until datalink technology became prevalent it was the only way for ATC to work over the Atlantic: voice position reports, via HF, to the radio stations at Gander and Ballygireen who then relay the messages to the actual ATCOs (who in the case of Shanwick are located in a different country -- some 400 miles away at Prestwick).

Obviously on VATSIM at present CPDLC use and availability is limited, which means we are stuck primarily with voice position reports until such time as the technology is developed to simulate CPDLC in a more integrated way (mainly on the pilot side).

Yes, VATSIM use VHF frequencies, but only as a substitute because there are no HF radios in MSFS (that can be seen by a pilot client). This is a very minor concession to realism to overcome a core sim limitation, but that aside, as I have said already, the procedures in use are accurate. I'm sure if there was a way for an HF radio to be tuned and selected in the pilot client then HF frequencies would be used instead.

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3 hours ago, downscc said:

As a communications engineer experienced in HF radio, I can assure you this is routine stuff.  Our USAF aeronautical station was at RAF Croughton, NE of Oxford, and from there we could talk to aircraft anyplace in the N Atlantic including AF One (at the time, before satellite). Why do you doubt that?

Let me go off topic here to wish you well, Dan. Be safe out there in KCRP!

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Simon.

I know you could with HF, relay and all that, ive heard of stories of people picking up manilla  in the philipines when on HF in the atlantic because of the sun etc etc etc...

I also know you can reach people with cpdlc and selcal etc etc, but with VHF, as you rightly said its line of sight.  The equation is as below.

d = square root (h^2 + 2hr)
where:
h = height above earth's surface
r = earth's radius = 6371km or 19418808ft

1000 FT = 32.4 NM
10000FT = 102.5 NM

This gives the visible horizon from one point. If you want to figure out the range between 2 elevated objects, then add together the 2 values of d.

So that would make it
d (in NM) = 1.025 x square root height in feet

 

Theres no way you can get VHF 133.00 or whatever vatsim use for gander or shanwick at 30w especially in the southern atlantic.

Id love vatsim to implement HF and CPDLC but they dont.

Cheers.

 

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34 minutes ago, tooting said:

Id love vatsim to implement HF and CPDLC but they dont.

I'm sure VATSIM would love to implement HF too. But the question is when will LM or DTG implement HF so that we can have a radio that can actually be tuned?!? (CPDLC, for what its worth, is already implemented pretty well using Hoppie's ACARS system and fully integrated in to controller clients: the question could also be asked, when will aircraft developers integrate it in to their FMCs so that it can be used properly to its fullest extent?)

For about the third time: nobody is pretending, or ever has pretended, that the VHF frequencies themselves are accurate. But in the absence of an HF radio in the core sim, they are all we have!

The HF voice procedures are simulated accurately. In the absence of a tunable, externally-readable, universal HF radio in the sim, a concession has to be made and a VHF frequency (with, indeed, some trickery on the controller setup side because the VHF range in FSD is accurately simulated with reference to the formula quoted) has to be used. To me, and most others, that is a very minor workaround to enable us to have what is an otherwise perfectly realistic service.

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