EC120 elec system Q..
Thread Starter
EC120 elec system Q..
Hiya,
currently doing an EC120 typerating in EASA-land, Does somebody have a diagram or a link to an explanation what the EMER SW does/isolates on the 120?
none of my available docs mention it except in certain checklists..
many thanks
currently doing an EC120 typerating in EASA-land, Does somebody have a diagram or a link to an explanation what the EMER SW does/isolates on the 120?
none of my available docs mention it except in certain checklists..
many thanks

If fitted and actuated, the EMER SW cuts all DC power except for the following items powered direct from the battery: Engine, NR/Nf instrument, Emergency lighting (Map lights). The systems description (Page 7-31 in the RFM) states:
It's used for Smoke In Cockpit / Cargo emergency drills etc.
In case of an electrical emergency, after actuating the [EMER SW] (If fitted) in cut-off (down) position, all DC power is switched off except some vital consumers directly fed by the battery:
- The engine,
- NR/Nf instrument,
- Emergency lighting (Map lights)
- NR/Nf instrument,
- Emergency lighting (Map lights)
Excuse me asking, but is your type rating not being taught by a TRI who might know that kind of stuff?
In the case of the EC120, the EMER SW was an option and also was subject to SB after it was found to do the opposite of what is was supposed to do so unless the PowerPoint was updated, it was probably not briefed. If your TRI (or likely FI in this case) has never flown an EC120 with that particular mod, it's not surprising they might not know, although given its in the FLM its not much of an excuse.
I think you overestimate the quality of some Type Rating courses. One I did recently hadn't been updated in 15 years and was missing whole chunks because it wasn't included in the original "day 1" training notes the company have received at the factory.
In the case of the EC120, the EMER SW was an option and also was subject to SB after it was found to do the opposite of what is was supposed to do so unless the PowerPoint was updated, it was probably not briefed. If your TRI (or likely FI in this case) has never flown an EC120 with that particular mod, it's not surprising they might not know, although given its in the FLM its not much of an excuse.
In the case of the EC120, the EMER SW was an option and also was subject to SB after it was found to do the opposite of what is was supposed to do so unless the PowerPoint was updated, it was probably not briefed. If your TRI (or likely FI in this case) has never flown an EC120 with that particular mod, it's not surprising they might not know, although given its in the FLM its not much of an excuse.

But I find the reality is that a groundschool for a type is written on first contact with an aircraft by an ATO and purely from the manufacturer notes. The tips, unwritten knowledge, photos taken during deep maintenance and modifications don't get added.
It's also nice when the type rating exam (should a written one be given due to the size iaw the regulations) is actually correct and also not just a quiz on numbers which are colour coded on the guages anyway.
Thread Starter
Fair question and apart from a rather vague sentence in the RFM, there is not much that covers that particular item, even in the factory teaching materials. (I have the older stuff, not privy to new and current stuff..)
I was wanting to see a diagram of what it does so I can answer that question in the oral part of the checkride, my CFI did say exactly what it says in 7-31 but being the diligent type, I wanted a colourful picture if it was available somewhere
.
On the subject of typeratings, its the same over in the bizjet world where providers outside the factory training also have gaps in the material or when flying the aircraft you find out alot of stuff is “completion centre items” and hence your instructors have no clue what you are on about…
I was wanting to see a diagram of what it does so I can answer that question in the oral part of the checkride, my CFI did say exactly what it says in 7-31 but being the diligent type, I wanted a colourful picture if it was available somewhere

On the subject of typeratings, its the same over in the bizjet world where providers outside the factory training also have gaps in the material or when flying the aircraft you find out alot of stuff is “completion centre items” and hence your instructors have no clue what you are on about…