PPRuNe Forums - View Single Post - to prevent a hot start!?
View Single Post
Old 4th Mar 2002, 06:53
  #11 (permalink)  
Buitenzorg
 
Join Date: Mar 2002
Location: West of zero
Posts: 240
Likes: 0
Received 0 Likes on 0 Posts
Post

On the B206 I've encountered 4 main factors causing hot starts:. .- pilot technique/just not paying attention;. .- weak battery;. .- bad fuel control;. .- faulty bearing in throttle linkage causing a very stiff and hard-to-move twistgrip.. .. .With a little experience in type a weak battery will be obvious when you push the starter button from how rapidly the igniter clicks and how fast the engine spools up. Also a good sign is the fuel pressure gage: if fuel pressure drops to almost 0 as soon as you hit the starter, that's a sure sign of a weak battery. JetRangers with their small batteries have problems than LongRangers (both NiCad types). NiCad batteries aren't meant to sit for long periods in charged state, so if your battery was serviced (deep-cycled) a month ago, charged, and then fitted in the aircraft that then didn't fly for a month, it will be in poor state.. .. .A bad fuel control with cause high TOT peaks during the start sequence, and the only way to find that out is to start it. To avoid a hot start under these circumstances set some hard limits for yourself and follow them. For instance, on the C30P LongRanger (modulated start) I start backing off the throttle when the TOT climbs above the yellow, and abort if it goes over 823C. A long way from the absolute limits I know, but at $15,000 for a new turbine wheel I don't get many complaints. Eventually the fuel control will have to be replaced.. .. .A certain bearing in the throttle linkage, I can't remember exactly which bearing it is, tends to go bad, which will make the twist-grip very stiff and hard to move small amounts - a real problem on a modulated start. Mechanics with some experience on the B206 will know which bearing to replace.. .. .The key to avoiding hot starts is to know the limitations, set your limits, watch that TOT/T4/ITT/whatever like a hawk, and don't be afraid to abort the start. Oh yes, and be nice to your mechanics. <img border="0" title="" alt="[Wink]" src="wink.gif" />
Buitenzorg is offline