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Re: Chieftain Prototype Build
Posted: Sat Aug 24, 2019 7:04 pm
by Stephen White
The GUE or “genny” was essential to start the Main engine. Thereafter, in theory you could switch it off and the ME generator would sustain the load. In practice we never ran on ME only out of choice. More usual was to switch off the ME and use the GUE whilst the radios and gun kit were operating. We could then go to a silent watch, as long as you didn’t need the light projector. I’m sure Mark will comment more knowledgeably as wiggly Amos was his trade.
Re: Chieftain Prototype Build
Posted: Sat Aug 24, 2019 7:13 pm
by Manny Leung
Does a chieftain engine sound the same when running on diesel or petrol? Or can you tell by the sound which fuel it is on?
Re: Chieftain Prototype Build
Posted: Sat Aug 24, 2019 8:47 pm
by Stephen White
Manny, I doubt there are many people alive who have ever heard an L60 running on petrol. I certainly haven't. In a couple of decades on the tank, I never filled up with anything other than diesel. The biggest element in the overall sound of the engine is the exhaust note and that isn't dependent on fuel. I can't think of any reason why the choice of fuel might affect the sound of the tank, unless you tried using chicken s..t.
Re: Chieftain Prototype Build
Posted: Sun Aug 25, 2019 11:45 am
by Kevin Hunter
That really is an amazing sound, I hope the electronics can do it justice? Looks like the smoke generator(s) will have a bit to live up to as well
Kevin
Re: Chieftain Prototype Build
Posted: Sun Aug 25, 2019 5:02 pm
by Mark Heaps
For Vince & Stephen,
The crews were taught to start the GUE first as best practice, the coolant would start circulating to pre-warm the ME and the output from the GUE would reduce the load on the hull batteries when starting the ME. The hull batteries were four 100 AH in a series paralell configuration to give 24V 200 AH. If the hull batteries were in good condition with a good state of charge, the ME could be started without the GUE running and on-line. The GUE was not essential but it was good that the crews thought it was, it re-inforced best practice.
Theoretically the GUE could have been switched off once the ME was started and the ME Gen on-line, but there was no reason why you normally would want to do so. Having both generating systems on-line, either of them could fail and it would not affect the fightability of the tank.
The only reason I can think of where you might shut the GUE down after having started the ME, is if the GUE had a coolant, fuel or oil leak and you were using it for the shortest period possible to get the ME started.
Mark
Re: Chieftain Prototype Build
Posted: Sun Aug 25, 2019 8:29 pm
by Vince Cutajar
Thanks for the info. I thought it would be used similarly to an aircraft APU but it seems I was wrong.
Vince
Re: Chieftain Prototype Build
Posted: Mon Aug 26, 2019 6:59 pm
by Mark Heaps
On Chieftain, the GUE generator was rated at 150 amps and the ME generator was rated at 350 amps. If both systems were on-line, the generator panels did load balancing so each generator would be proportionally loaded to get the total output required.
Challenger 1 & 2 had higher rated GUE generators, the generator panels would work to load the GUE generator to the max before loading the ME generator to cover any excess required. Any electrical load on the ME would mean less power for automotive purposes.
If I recall correctly, the GUEs only got the designation APU´s with the introduction of Challenger 1 to differentiate between the two fits, ie a Chieftain GUE would not fit in a CR1, and a CR1 APU would not fit in a Chieftain ARRV. Both vehicles operating side by side.
Mark
Re: Chieftain Prototype Build
Posted: Fri Sep 06, 2019 12:07 am
by Armortek
Rubber inserts for the Chieftain tracks getting counted out and packed.
Re: Chieftain Prototype Build
Posted: Sun Sep 08, 2019 11:41 pm
by Armortek
A few more photographs of the Chieftain.
Re: Chieftain Prototype Build
Posted: Mon Sep 09, 2019 7:14 am
by Stephen White
It’s impressive, superb even. Looking forward to seeing it, if not hearing it at the Open Day. Some hull back bins would fill a space or two.
Re: Chieftain Prototype Build
Posted: Mon Sep 09, 2019 8:11 am
by mark lawson
This is certainly Armortek's finest model thus far.
Re: Chieftain Prototype Build
Posted: Mon Sep 09, 2019 9:11 am
by John Clarke
WOW
Re: Chieftain Prototype Build
Posted: Mon Sep 09, 2019 9:35 am
by Armortek
Stephen White wrote: ↑Mon Sep 09, 2019 7:14 am
.............. Some hull back bins would fill a space or two.
They are on the production version, but not the prototype. Same with the ribbing on the bins.
Re: Chieftain Prototype Build
Posted: Mon Sep 09, 2019 10:25 am
by Kevin Hunter
Phew !!
And the bow wave deflector ?
It looks awesome. Well done to all involved.
Kevin
Re: Chieftain Prototype Build
Posted: Mon Sep 09, 2019 12:41 pm
by Gerhard Michel
Just some thoughts about tank engine sounds and their reproduction in models like 1/6 scale:
1. A real tank sounds very differently at front, side or rear view when passing a person. A model with its sound source down below cannot reproduce these different sounds for a listener. Therefore it is a little tricky to find a suitable sound pattern for a model
2. Loudspeakers can reproduce the deep frequencies of tanks and their engines only with large dimensions which don't fit a model. Therefore it is better to use one big speaker than two smaller ones. Unfortunately most amplifiers are 2-channel-types which don't allow to use their 2 channels parallel at one speaker. Using only one channel results in half the output power. A possible solution is to use a speaker with 2 moving coils, another solution could be a dedicated car amplifier with a subwoofer option to bundle two channels to one.
3. To compensate the lower effectiveness of a small speaker at low frequencies it is possible to intensivy these frequencies previously by audio processing. Unfortunately this procedure also encreases the power consumption. A tank engine sound in a model, reproduced close to the original, has a power consumption which clearly exceeds the main engines! Therfore a seperate power source ist necessary for the amplifier, needing additional space.
The best (and loudest
) reproduction of a tank engine sound I ever heared was Olaf's Panther in 1/4 scale with a 40 cm subwoofer, 2.000 watts power amplifying and a 40 Ah power source only for the sound! But with its 100 Ah driving power the model runs significantly longer than it sounds........