starter warning light

[buzzc152]

If the starter warning light didn't go out immediatly after start (say it stayed on for 15-20 secs after start then went out), what could this signify and what would you do about it ?

Thanks:(

[Tall_guy_in_a_152]

My response as a PPL and electronics engineer, NOT certified aircraft engineer / technician.....

The warning light means that the starter motor is still spinning. This could be because it has not disengaged from the engine, or is still being supplied with power (e.g. dodgy switch). In the former case, it implies that the engine is spinning the electric motor rather than vice versa. This will burn out the motor (and any other drive mechanisms in between) fairly quickly and possibly seize the whole thing up. In any case, the engine will not develop full power.

That is not good!

The light should go out within about 2 seconds. Otherwise shutdown the engine. Do not wait to see what develops and certainly do not fly or even taxi.

As to what to do next, well, I'm not an aircraft owner so I don't know.

TG

[topcat450]

Yup I'd have said similar. Sounds like the starter motor and engine haven't disengaged from each other. I've always been told to shut down immeditatly if either starter motor warning light stays on OR oil pressure doens't start to rise immediately after starting up, and 20 seconds is a long time in my book for the light to stop on. ( I was thinking about C150s but I imagine most a/c are the same)

I'd shut down and collar an engineer to have a look, or tell the club your renting off you want a new plane.

[QDMQDMQDM]

If they're so essential why aren't they standard on foreign aircraft? If you import an aircraft to the UK you invairably have to put one in at great expense.

QDM

[rustle]

QDM sure you're not thinking of the "low voltage" light?

[QDMQDMQDM]

No, I'm sure it's the starter warning light.

[Evo]

http://www.pfa.org.uk/pdf_docs/engineering/information_leaflets/2ndhand_imported_inspection.pdf

says that


If an electrically operated engine starter and solenoid are fitted a starter warning light is required. CAA Airworthiness Notice No.33 refers.

[rustle]

Oi, Evo, that's twice in two days ;)

BTW,

CAA Airworthiness Notice No. 88 requires a single-engined aircraft equipped with an engine driven electrical generating system to be provided with a clear and unmistakable warning to the pilot that the alternator or dc generator output voltage has fallen to a level where the battery is supplying power to the electrical loads....See: http://www.caa.co.uk/docs/33/AIL0130.pdf

Naah, naah, na-naah, naaah! :O :ooh:

[Evo]

I didn't know what the fuggin' light meant or what I'd do if I got to 'starter warning light off' in the checklist and it wasn't, so I tried to look it up. Took me more than 8 seconds to find it though :)

I did know about the low voltage light, but it doesn't apply to aircraft on a permit to fly - you did read that fascinating link of yours, didn't you? ;) :p

[rustle]

"...but it doesn't apply to aircraft on a permit to fly"

You can't throw a curve-ball (permit types) and automatically "win" ;)

Based on the original posters PPRuNe name, I'm guessing it ain't a permit aircraft he was asking about! :p ;)

[Tall_guy_in_a_152]

Ah ha.

So if the starter warning lamp is an 'after market' add-on, that would explain why they are mounted in different places on the panel of all the aircraft I rent. I often wondered (briefly) about that.

TG.

[A and C]

The warning light tells you that the starter motor is still conected to the rest of the electrical system.

It my be spinning very fast and not conected to anything.

It my be conected to the engine and acting like an alternator and feeding unregulated current into the electrical system.

The first action is to stop the engine with the mixture and you may have to stop the starter motor by turning off the master switch.

[ACX]

The starter warning light is not actually fitted to tell you that the starter is engaged. It actually shows that the stater solenoid is made.

The warning light is wired across the starter solenoid and lights up when power is supplied to the solenoid, i.e. on hitting the starter. If the solenoid jams in the engaged position it will quickly become very hot, and I mean hot. Jammed starter solenoids have been known to become so hot, that in one instance I know of, it melted its way through an oil tank, resulting in fire and total loss of the aircraft. The starter solenoid is not designed to take continous power, but rather intermittent. They should not be confused with the battery solenoid which is designed to take more power over a longer period.

The light should (must) go out as soon as you release the starter switch or key. If it stays on the solenoid may be sticking and should be investigated.

If the actual starter sticks in the engaged position the light will go out. You may be lucky and hear the tell tail high pitched whinning noise. In which case you case shut down. If not it will spin itself to death.

AC&X