Master Caution Light

[Chocuk]

Hello everyone,

Master caution light is no-go item? What happens if one of them does not illuminate? I’ve checked b737 DDG but it doesnt say anything about mster caution lights, DDG only says about annunciator lights.

Regards

[deltahotel]

Not sure if this helps but 757 MEL says: One may be inoperative provided master caution aural system and all discrete caution lights operate normally.

[Australopithecus]

737 DDG Does not list the two master caution lights but does specifically allow one of the 12 in the six packs to be inop. As you know, if a component is not specifically listed in the MEL it is then required. Two functional master caution lights are hence required, which makes sense given the primitive 1950’s design.

Unlike modern aircraft the 737 has no audible caution alert apart from fire bells.

[FlyingStone]

Master caution light is no-go item? What happens if one of them does not illuminate?

It is. You don't go until it's fixed?

[dixi188]

Don't know about your 737 DDG, but for all the aircraft I have worked on, if something is not mentioned in the MEL then it is a no go item.

[Miles Magister]

You must read the pre-amble of your DDG/Mel. If an item is not mentioned in the MEL then it is automatically a no go failure as it is required for airworthiness.

MM