Whilst serving/holidaying in Belize I was roped in to help prepare this Harrier GR3 for presentation to the people of Belize!





















Well your occupation was certainly more interesting than moving miserable commuters from A to B !
Aceyone wrote::))Well your occupation was certainly more interesting than moving miserable commuters from A to B !


The above is soo typical ! 

Gaz wrote:ooops!!
Nice pics though, Dave!


Xplumberlives wrote:Gaz wrote:ooops!!
Nice pics though, Dave!
No OOOPS about it, I'd done my checks!








all round 



Xplumberlives wrote:Siemens!!




Hydealfred wrote:Can somesone tell me what the strange sound is that Desiro units make as they move off ? Sounds very Sci-fi![]()
Sorry I've gone a bit off thread here




Hydealfred wrote:Can somesone tell me what the strange sound is that Desiro units make as they move off ? Sounds very Sci-fi![]()
Sorry I've gone a bit off thread here



RLN wrote:It's actually the control electronics that make the traction motors work that make that noise.
Networkers and Cl323's use Gate Turn-Off (GTO) Thyristors which is why they sound like they're changing gear as they accelerate and brake using the regen brake. Newer stuff like Electrostars and Desiros use the next technical development called an Insulated Gate Bipolar Transistor (IGBT). It does the same job as a GTO Thyristor but uses less current, switches faster and can be made smaller and lighter. They also sound very different making more of a whining noise.
Simples
Wanted to know for ages but hadn't found anybody that knew the answer, as not even people who work on 350s
knew exactly what caused the sound as the units accelerated away from the platform... 




RLN wrote:TBH, I only googled it

I know nothing - and anyway, I don't do that small wire stuff. 




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