Go Back  PPRuNe Forums > Ground & Other Ops Forums > Engineers & Technicians
Reload this Page >

King Air C90 Propeller Balence

Engineers & Technicians In this day and age of increased CRM and safety awareness, a forum for the guys and girls who keep our a/c serviceable.

King Air C90 Propeller Balence

Old 20th Oct 2015, 12:44
  #1 (permalink)  
Thread Starter
 
Join Date: Jun 2008
Location: Manchester
Posts: 17
Question King Air C90 Propeller Balence

Can anyone give me some guidance on this matter,
There is no mandatory Requirement (That I can find) for carrying out a dynamic propeller balance on the C90, However the procedure for carrying this out is listed in Chpt. 61.
In this procedure it gives a range of allowable IPS. of vibe.

1. Is there a listed interval (ie. at Prop change)

2. How do I determine the IPS with out carrying out a dynamic balance ?

Thank you in advance for any input

Fleep

Last edited by Fleep; 20th Oct 2015 at 13:05.
Fleep is offline  
Old 21st Oct 2015, 06:28
  #2 (permalink)  
 
Join Date: Jun 2009
Location: South East Asia
Posts: 410
King Air C90 Propeller Balence

Let me say from straightaway that I'm not a fixed-wing person but I believe my experience with helicopter rotor balancing gives me some limited authority to suggest an answer to your query.


Both prudence and 'best practices' dictate that you should perform dynamic propeller balancing upon installation of a new prop and reinstallation of the existing unit. Don't forget to index the prop to the flange and clearly highlight the attached balance weights so that other maintenance personnel don't move them. Subsequent to this, further dynamic balancing should be performed whenever you have a suspicion that it is required.


If the aircraft is flown by a number of different pilots, sooner or later one of them will comment on the propeller vibration level but if you're the only pilot then you may not notice the gradual rise in the vibration level and this is when it's best to establish an interval to accomplish the task. I would suggest you start at 200 hours and see what you get. If the IPS is essentially unchanged then extend the interval to 300 hours and so on.


One point to note, when you're performing the dynamic balance DO NOT stop when you reach the 'acceptable' IPS - keep going and get it as low as you possibly can - the airframe will thank you for it - a truly smooth rotor/propeller greatly enhances the reliability of structure and components.


Finally, your question "How do I determine the IPS with out carrying out a dynamic balance?" I believe the only way is to put the equipment on and do a run.
Saint Jack is offline  
Old 21st Oct 2015, 12:42
  #3 (permalink)  
Thread Starter
 
Join Date: Jun 2008
Location: Manchester
Posts: 17
Thanks for the reply Jack.
I come from a heli background also, therefore appreciate the benefits of smooth operation of rotating components.
Hartzell CMM standard practices only Recommends Prop Balance, But it does not specifically require it, Neither do Beechcraft, so this customer will always take the easy/cheaper option. Sadly!
Fleep is offline  
Old 22nd Oct 2015, 21:07
  #4 (permalink)  
 
Join Date: Jul 2013
Location: Las Vegas NV.
Age: 60
Posts: 165
Every time we hang a prop on a KA, we dynamically balance it, no ifs ands or buts. We've gotten props back fron the shop that have tested at 4+ ips.

All that shaking is hard on the airframe and the people in it.
LASJayhawk is offline  

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information -

Copyright 2021 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.