Tail deice boot - W&B info

[Jim Rainer]

Trying to locate W&B information. I have a 1976 normally aspirated 337 SN 1743. Wing de-ice kit intalled after delivery on a form 337. The description on the form 337 says this:

" Installed wing de-ice system cessna part number SK 337-149D. All work accomplished per installation instructions applicable Cessna service manual and FAR's."

The W&B form attached to the form 337 has only this info:

WT ARM MOMENT"
"WING DE-ICE KIT 30.1 136.8 41177

There is no mention of the tail boot being separate from the wing boots. Due to its deteriorated condition, I had my A&P remove the tail boot, seal the tubes and install an abrasion boot. I may eventually replace the tail boot but not soon (my de-ice system is labelled 'inopertive' or some such language and the circuit breaker is sealed open.) We can find no official iinformation about the weight and arm of the tail boot. We can weigh the remains and determoine its arm, I suppose, but I'd rather have something official. Anyone got any specific informaiton that might help us?

GMAS, this is right down your alley.

[GMAs]

Well the first question first... if they put the kit from cessna on.. then cessna should have it listed on their wt and bal sheet... for the skymaster... i.e how much does each part add to the wt and what station and water line does it go at...to...

You can contact any Cessna parts place and they should be able to tell you what the kit come in at... in wt... and each part....should be broken down... such as the boots...

Now they usually don't break each part down into left wing, right wing, elevator... when it is a kit and as such it was supposed to all be thier... and removal of one part is usually not done... but,...

If you cant get cessna to send you the wt and bal parts of the installation kit... which they should... you can go it a different way....

You can weigh the part removed... and the part put back on... such as your impact strip... subtract the strip from the original and that is the weight change... now you can go thru the wt and bal formula and determine if it has a impact..effect... and make a note in the log book along with a 337 form saying it was removed... with the new wt and bal... and so long as its within the limits of the wt/bal.. for your plane... your OK... have your mechanic file the 337 form and everyting should be happy again...

by the way.. you all know how many copies of the form you have to sign right... if you say 3 your right... 1 goes to the FAA.. one for the owner... and one for the log book.... if the mechanic or IA wants a copy he can make a photo copy... but, you should only sign 3 copies... and I once had the question... how do I know if the FAA gets it... well they have to sign after you... so either you or your mechanic have to make a trip down to the FAA office... either way.. you should be getting back two copies... its important that you file the owners copy.. in a safe place.. the other goes in the log book that stays with the plane... and no you can't use a copy... signature have to be original...

Now if you don't have the original wt and bal sheet (which should have come with the log books...when you bought the plane) you can write cessna.. and they will send you another one that is a copy of the original that they gave out from the factory for your plane... ya they get lost... but, remember it won't have any of the additons or 337 forms stuff that was added or taken away... it will only be the way it came out of the factory new....

Another way is to go to the TCDS and look it up also.. but, its better to use the factory sheet and work up or down from their... that along with the kits wt and bal for your plane.. and your back in the good side... yes the third option would be to re-weigh the plane... but, that is going to require some expensive equipment... and time...

Now as to the rest.. yep it was placarded as being out of service... and has to remain such until the rest of the system is put back on line with the elevator part working... you can't have a partial system .. as it was a kit installed... and the placard and lock out of the system has to be their till it is repaired or replaced...


As to their entry in the form and book... I wonder where it says to install the kit in or per the service manual... or FAR's... I think he didn't do a good job here.. as it should have read.... Installed kit per cessna instructions for kit*******... dated NNN NNNN. Cessna usually puts all the information that you need in the instructions that come with their kits...

then if he had to use any other things such as installed hardware that is common... it should read on the bottom...
All other work not covered by the installation kit was done in accordance with 43.13 1&2 Acceptable .... dated NNN NNNN... citing the paragraph and page for the items...

This is usually the standard entry and not as he had put.. but, it would get by...

Your numbers that seem to be on the sign off are 30.1 lbs at station 136.8... the 41177 is the moment/in/lbs.. change.

Hope that this helps... as each kit is really a little different in weight as the manufacture buys from several different ones... so compairing it to someone elses is not really what you want to do... If you get stuck come back... its important that you get your wt and bal records correct... GMAs

[Jim Rainer]

Thanks, GMAS. As usual your expertise is a big help!