circuit breakers

[Guest pokey]

The topic came up a while back about re-setting circuit breakers in flight. ( reason it came up is that guy here has a Russian seaplane, that has ALL the circuit breakers locked in a fwd baggage compartment-NO access in flight, unless you dare crawl up the side of the fuselage)

 

A few airline pilots say that its standart procedure that if a breaker pops in flight- DO NOT try & re-set it.

 

A bunch of 300's that i know of ( older ones) if you have landing light on for extended period of time, it will pop the breaker----so this means we should try landing in pitch black & for sure wreck, rather than re-set the breaker?

 

Interestingly enough too, the regulations state that any breaker required for safe flight must be accessable to the pilot,,, which when you think about it? it doesnt state how long this "safe flight" is to last & it doesnt say anything about a safe landing.

 

Anyone have company policies? personal thoughts/experiences?

[PhotoFlyer]

Breaker pops, reset...

 

Breaker pops again, don't try to reset...

[67november]

agreed, disable breaker with tie wrap as reminder to tell mechanic.

[delorean]

If possible, turn off the appliance first, reset the breaker, then turn the appliance back on. If it pops the breaker, turn it back off and don't push the breaker back in.

[joker]

BrA few airline pilots say that its standart procedure that if a breaker pops in flight- DO NOT try & re-set it.

 

Generally disagree. Also, your emergency checklist may call for the resetting of the CB. S76 has many instances where resetting is required by the checklist. Particularly with Chip Lights or AP CBs.

 

A bunch of 300's that i know of ( older ones) if you have landing light on for extended period of time, it will pop the breaker----so this means we should try landing in pitch black & for sure wreck, rather than re-set the breaker?

 

There is no right answer to this. Its a judgement call. If you are in the darkest night, and your landing light CB blows, then for sure I will try to reset it. If I'm in broad daylight, then I might choose to leave it until on the ground.

 

If possible, turn off the appliance first, reset the breaker, then turn the appliance back on. If it pops the breaker, turn it back off and don't push the breaker back in.

 

Delorean's advice is good. Here are some more tips to aid in your risk assessment:

 

'Weigh up the risks', but understand them.

 

1. CBs are designed to pop. That's what they are there for.

2. Resetting a CB on a faulty circuit should just make the CB pop again with no harm. One pop may be just bad luck, and worth trying to reset. Two is probably a faulty circuit and should be left.

3. Don't keep trying to reset a popping CB, as you will probably be causing a short grounding somewhere, which could lead to fire or further damage.

4. In the most unlucky cases, resetting a CB on a faulty circuit may aggrevate a problem or cause another problem. Ask yourself, "Do you feel lucky?!"

5. If an emergency checklist calls for it, reset it of course.

6. If you don't need that item, then don't reset it....see 3!

 

 

I have heard all different ideas on this subject. General concensus is to leave them. However, personally, I don't agree with wire ties on them, until the end of the flight. In flight, I wouldn't wire tie anything.

 

Reason for this is that, you may a) need that equipment so bad later that you accept the risk to try it again later in the flight, or Find that the actual cause was not that equipment but some other equipment. Then you have just disabled some working equipment.

 

Joker

 

P.S. Quotes working now....thanks Gomer....it was obviously too late for me!

[Gomer Pylot]

Your 'QUOTE things' don't work because the first one isn't closed. You start off with a

.....

which confuses the HTML parser.

 

I generally agree with your post. Read the checklist and do what it says. That's why they put the checklist in the aircraft in the first place. Use it.

[Guest pokey]

Here is my take on the situation , which is more or less along the lines of the general population here: If the breaker pops on appliance you need "immediately" re-set immediately,( if it pops twice?--initiate Plan B ),,, if it can wait? then wait-but i wouldn't tie it off & cut out my chances of using that appliance at a later time. Remember what a circuit breakers main purpose is: "to protect the wiring". When wires heat up, OR appliances try & draw more amps than the wiring can handle?--they "pop"

 

I've never flown any "fancy" aircraft, so i dont recall any circuit breaker reference in the checklists other than "check circuit breakers"----any one have any "real-time" specific reference to a checklist we could hear about?

 

And the ariline pilots that i was referring to? i believe they said it was "company policy" NOT to re-set a breaker in flight, altho they were defending that Russian seaplane that has them "inaccesable" to the pilot in flight.

 

Last question: What do you think about an aircraft with the breakers NOT being accessable to you ( the pilot) in flight?

[Gomer Pylot]

The AS350D was pretty much that way, except it had very few breakers. It has(d) a lot of fuses, though, which were more or less accessible. Trying to change fuses while flying was an interesting experience, though. At least one of the fuses ( I can't recall exactly which, it's been a long, long time) had a very strong spring, and if you didn't contain it when you unscrewed the cap, the cap and fuse would fly out and ricochet around the cockpit. The AS350 wasn't designed, it was just thrown together out of old Peugeot parts. We don't need no steenkin' gauges..........

[jet trash]

As far as Airline flying and circuit breakers go, the FAA came out and had us stop reseting CB's. This was supposedly because of TWA 800 and a few other accidents where electric lines over heated.

 

The FAA recommends not resetting a popped CB unless the abnormal/emergency procedures call for it and guidlelines are followed.

[joker]

Classic Questions:

 

How many CBs in the Schweizer 300CB?

 

Show me the spare fuese (as required in 91.205) in the R22 BII

 

Amazing how these two questions would stump many of the people I asked.

 

S76 C+ Emergency Checklist

 

INT/TAIL GB CHIP/HOT LIGHT ON

 

1. CHIP DET I/TGB CB........................................PULL AND RESET

If light remains off:

2. Continue flight and advise maintenance.

If light comes back on:

3. Land as soon as possible.

If loud noises or high vibration levels occur:

4. Land Immediately.

Anticpate loss of tailrotor thrust

5. Emergency checklist.......................................COMPLETE

 

Other Emergenency Items which require pulling or reseting CBs in flight are:

 

MGB CHIP LIGHT ON

INVERTER CAUTION LIGHTS ON

DC GENERATOR LIGHTS ON

SERVO JAM CB (Use with caution)

LANDING GEAR WILL NOT EXTEND

 

Joker