citation engine questions
Thread Starter
Joined: Jul 2003
Posts: 265
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From: germany
citation engine questions
Hi to all, I fly a citation cj1+, we consequently alternate the engines for starting L - R - L - R unless wind conditions dictate, which engine to start first.
Do you guys do this alternate starting too or is this some kind of obsolete ritual?
BTW, one technician recently told me to turn the fans once a week if no flight takes place. Never heard about that before, opinions are welcome!
Cheers
Cecco
Do you guys do this alternate starting too or is this some kind of obsolete ritual?
BTW, one technician recently told me to turn the fans once a week if no flight takes place. Never heard about that before, opinions are welcome!
Cheers
Cecco

Joined: May 2005
Posts: 1,198
Likes: 32
From: France
Hi Cecco,
I'm not sure that alternate starting makes a lot of difference. On the other hand, it probably doesn't do any harm either.
As far as regularly turning the engine is concerned; this is definitely a good idea as corrosion will build up in between the stator case and the high pressure compressor blades after shut-down. If not 'polished off' by turning the rotor every 4 weeks or so, this corrosion can build to such an extent that it will eventually seize up the whole engine.
Remember, these engines were designed to be used once only - powering a cruise missile!
I'm not sure that alternate starting makes a lot of difference. On the other hand, it probably doesn't do any harm either.
As far as regularly turning the engine is concerned; this is definitely a good idea as corrosion will build up in between the stator case and the high pressure compressor blades after shut-down. If not 'polished off' by turning the rotor every 4 weeks or so, this corrosion can build to such an extent that it will eventually seize up the whole engine.
Remember, these engines were designed to be used once only - powering a cruise missile!
Joined: Mar 2002
Posts: 4,569
Likes: 1
From: Florida
Remember, these engines were designed to be used once only - powering a cruise missile!
Perhaps there is something in the limitation section to say they should be hand-turned between flights ?
Joined: Mar 2010
Posts: 269
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From: NW
Cecco - Yes, excellent....you also need to sit in all the seats, run them forward and back, side to side, and move all the seats around to make sure they stay 'movable'
Look and move the Wemac air vents...left, right, forward, and back for all overheads.
Make sure when you go flying only run 1 EFIS tube at a time, to save other tube life
Once a week, get in the plane, and wiggle the control, move the flaps....
Great stuff, get right on it...
Look and move the Wemac air vents...left, right, forward, and back for all overheads.
Make sure when you go flying only run 1 EFIS tube at a time, to save other tube life
Once a week, get in the plane, and wiggle the control, move the flaps....
Great stuff, get right on it...


Joined: Apr 2004
Aviation Qualifications: LAME
Posts: 2,281
Likes: 189
From: Dorset UK
I don't know about the CJ-1 but years ago a Turbo Commander that I was involved in maintaining had both engines HSI (hot section inspection) at the same time. No.1 had no damage but No.2 had to have a lot of rework.
This operator always started No.2 first and nearly always used batteries.
So the higher ITT due to battery start as opposed to Generator assist start almost certainly caused the damage.
If you are doing battery starts and alternating the engines then you will even out the damage to both engines, but wether this will cost less in the long run I don't know.
Hope this helps.
This operator always started No.2 first and nearly always used batteries.
So the higher ITT due to battery start as opposed to Generator assist start almost certainly caused the damage.
If you are doing battery starts and alternating the engines then you will even out the damage to both engines, but wether this will cost less in the long run I don't know.
Hope this helps.
Joined: Mar 2010
Posts: 269
Likes: 0
From: NW
Cecco - some other things to consdier..
Once in a while you should put the plane on jacks to test whether the gear will fall down..
When on the jacks...wiggle the controls, with your headset on, so you can simulate flying, that way your ready.....
Oh and by all means, crawl into the engine inlet to spin the vanes, as fast as you can, that way you will know if they will fall off when running the engines...
When on the jacks...wiggle the controls, with your headset on, so you can simulate flying, that way your ready.....
Oh and by all means, crawl into the engine inlet to spin the vanes, as fast as you can, that way you will know if they will fall off when running the engines...

Joined: May 2005
Posts: 1,198
Likes: 32
From: France
Hi again Cecco,
Just wanted to confirm that I was told about the engine corrosion problem by a couple of experienced, well-regarded mechanics who are both qualified on the CJ series and the Williams engine.
Coincidentally, at the time they were telling me this, a CJ had been left on the ground for about 4-6 weeks in a coastal location. The engines were started supposedly without checking for free rotation and apparently a hot start resulted.
So I think this is a serious problem which needs to be more widely known. Anyone from Williams care to comment?
Just wanted to confirm that I was told about the engine corrosion problem by a couple of experienced, well-regarded mechanics who are both qualified on the CJ series and the Williams engine.
Coincidentally, at the time they were telling me this, a CJ had been left on the ground for about 4-6 weeks in a coastal location. The engines were started supposedly without checking for free rotation and apparently a hot start resulted.
So I think this is a serious problem which needs to be more widely known. Anyone from Williams care to comment?




