Real HS Trident question...

[Macs]

Hi,
I guess this goes to Peter Mc. :I was curious as to how relatively long-range flights over water or areas of low radio navigation coverage were flown. Was the Trident ever fitted with INS (CIVA for example)? I understand the plane had used a Doppler system (That neat-looking map contraption in the main panel ), but apparently was not too accurate. Just curious,
regards,
Macs

[PeteP]

I was curious as to how relatively long-range flights over water or areas of low radio navigation coverage were flown.

Well, if you'll permit a reply from someone else, the answer to how the Tridents flew long-range over-water flights is "rather badly".

One of the most amusing pastimes was watching the Tridents from London to some Scandinavian destinations trying to keep to the centre line of what was then known as UA37 as they flew across the North Sea. Random scatter was probably the best description of their track keeping especially in high winds. You can't blame them, of course, because UA37 was delineated only by a VOR at each end - DVR in the UK and SVA, I think, on the Danish coast with absolutely nothing in between. To be fair, this problem didn't just affect Tridents. The 1-11s out of Manchester had the same problem finding UR4 - the further they got from the OTR VOR, the more the problem they had with keeping the centre line.

Oddly, that "random scatter" around the centre-line actually contributed in a small way to safety - if an error was made with a climb or descent, the chance of meeting someone coming the other way on an exact reciprocal were extremely remote. With the modern RNAV equipment now fitted to aircraft, they often appear as if they're running on railway tracks, so accurate is the track-keeping. So accurate, in fact, that serious consideration is now being given to programming in a small track offset error to the nav equipment to avoid the danger of exact reciprocal tracks! Obviously, the Tridents and 1-11s were well ahead of their time.
PP

[Macs]

Well, if you'll permit a reply from someone else, the answer to how the Tridents flew long-range over-water flights is "rather badly".

Not a problem, of course Pete!



Thanks for your explanation! Very interesting. Do you know if any were fitted with INS's? Just curious...
regards,
Macs

[TobyV]

If you'll permit a reply from someone else again, I dont think any were fitted with INS. The doppler map actually wasnt too bad fom what i have heard, considering the era and the available technology. I would imgaine, that what with first continental European routes and latterly shuttle routes, the majority of flying would be over land with radio type navigational aids, it probably wasnt seen to be a big issue at the design stage... but thats just my guess.

[Macs]

If you'll permit a reply from someone else again, I dont think any were fitted with INS.

Toby! Not a problem either! the latter response applies to anybody too!
Thanks for the info bro

regards,
Macs

[TobyV]

Theres a few more ex-trident pilots, engineers and now even a few DH/HSA/BAe engineers over on my forum http://www.classicbritishaviation.org so someone there might be able to give more definitive answers

[Macs]

Theres a few more ex-trident pilots, engineers and now even a few DH/HSA/BAe engineers over on my forum http://www.classicbritishaviation.org so someone there might be able to give more definitive answers

Cool ! thanks Toby,
regards,
Macs

[petermcleland]

Sorry...bit late as I've been a bit busy...The Trident never had any fancy nav aids we just used VORs and NDBs and the Doppler (which was only right when the First Officer had put it right!).

The S111 on the other hand was wonderful in my time on the German internals...It had HARCO and flew the most precise tracks with wonderful anticipation of a waypoint turning point...It mattered not how big the angle was...It came out of the turn exactly on the going away track. We monitored the progress by tuning the VORs and ADFs and setting the OBS but the Autopilot just flew the whole sector HARCO was Decca based and we had a little leather suitcase full of "Turrets"...On entering the flightdeck, we just plugged in the Turret for this sector and it contained all the waypoints. :dance:

[Macs]

Sorry...bit late as I've been a bit busy...The Trident never had any fancy nav aids we just used VORs and NDBs and the Doppler (which was only right when the First Officer had put it right!).

The S111 on the other hand was wonderful in my time on the German internals...It had HARCO and flew the most precise tracks with wonderful anticipation of a waypoint turning point...It mattered not how big the angle was...It came out of the turn exactly on the going away track. We monitored the progress by tuning the VORs and ADFs and setting the OBS but the Autopilot just flew the whole sector HARCO was Decca based and we had a little leather suitcase full of "Turrets"...On entering the flightdeck, we just plugged in the Turret for this sector and it contained all the waypoints. :dance:

Peter,
Superbly informative as always! Thanks! Now you have me wondering about HARCO and DECCA . I found a site tha said some BEA Tridents used DECCA as a navigation aid, so was wondering about that, as well as what plane was the S111? Cannot find it. And One more question, If I am not grabing your elbow : What is the name if the weather radar used by the Trident? Just curious.
Thanks again.

regards,
Macs

[DaveB]

Macs..

S111 = BAC Super One-Eleven

ATB

DaveB :tab: