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

Weight & Balance and Microsoft Excel

Questions If you are a professional pilot or your work involves professional aviation please use this forum for questions. Enthusiasts, please use the 'Spectators Balcony' forum.

Weight & Balance and Microsoft Excel

Old 11th Feb 2016, 03:22
  #1 (permalink)  
Thread Starter
 
Join Date: Jan 2016
Location: NZ
Posts: 3
Weight & Balance and Microsoft Excel

Hey Team,

Does anyone have any information about the use of Microsoft Excel and A/C Weight & Balance Calculations? I can't find information on the FAA site that it can be conducted by using COTS Software, namely Excel.

Any assistance will be much appreciated!

Regards,
Alex
kazbak91 is offline  
Old 12th Feb 2016, 04:07
  #2 (permalink)  
Moderator
 
Join Date: Apr 2001
Location: various places .....
Posts: 6,567
If you can do it on a sheet of paper .. you can do it in Excel .. just be wary of errors in operation. Unless the system is approved for your Authority .. it will hold no more validity than doing it yourself longhand on a bit of paper ..
john_tullamarine is offline  
Old 12th Feb 2016, 11:11
  #3 (permalink)  
Moderator
 
Join Date: Aug 2006
Location: Ontario, Canada
Age: 59
Posts: 4,503
I can't speak to the formal approval of Excel as the W&B means, but I certainly have seen it used many times, and have used it myself for many different aircraft. It is my opinion that as long as you can demonstrate that you did an accurate and correct W&B, the authority is not going to question how you did it, as long as there is evidence that you did! (Print a copy)

I particularly like that you can condition the cells to give you red text if something is out of limits.

Always do a reality check of the outcome, does it make sense? Particularly if you're having to leave seats empty to make your C of G, does it seem logical? What do other pilots of that type say? I have found many errors in the basic W&B for an aircraft over the years, which resulted from errors at weighing, or calculation errors for small amendments. Most commonly are not weights, but errors in fuselage station locations for calculation, or scale location. If you're finding errors you can't explain, go back a few W&B for that aircraft, and review the results...
Pilot DAR is online now  
Old 13th Feb 2016, 05:25
  #4 (permalink)  
 
Join Date: Oct 2007
Location: Wherever I go, there I am
Age: 39
Posts: 690
kazbak91,

Your location says NZ...It was years and years ago, but when I worked at the Aero Club in Rotorua we used an Excel spreadsheet for W&B calculations on our C172's and PA28's. CAA seemed to think it OK and the regs in NZ paralleled the FAA regs at the time (I'm sure they still do).

IIRC, we did demonstrate to CAA that a simulated Excel calculation came to within a reasonable result of the same calculation done via the POH charts. That was done very informally during one of their routine visits. We spent more time talking about the smell in Rotorua than we did the spreadsheet, which should indicate just how much they cared.

It's too bad I don't have the spreadsheet anymore, or I'd send it to you. I do remember that we had to program the spreadsheet such that Excel did not round - I think it was one or two decimal points. Otherwise it would give us an out-of-balance result where the POH indicated it was (just) inside limits.
+TSRA is offline  
Old 17th Feb 2016, 19:20
  #5 (permalink)  
Thread Starter
 
Join Date: Jan 2016
Location: NZ
Posts: 3
It's just that from my regulatory perspective, if an excel spread sheet is used to compute W&B calculations, the failure of the software won't result in a catastrophic event IAW FAA FAR25,27,23 etc..1309 System Safety Assessment. By catastrophic I mean the loss of aircraft and life. However it is the unannounced misleading or incorrect information provided by the excel W&B calculations that can have aircraft level implications.


So if the crew insert the wrong take-off weight and speeds into the Flight Management System, from such erroneous calculations, the aircraft may not be able to take off in time...


Quite the tricky topic indeed.
kazbak91 is offline  
Old 18th Feb 2016, 02:46
  #6 (permalink)  
 
Join Date: Oct 2007
Location: Wherever I go, there I am
Age: 39
Posts: 690
That's where the reality check that Pilot DAR mentioned needs to come in. Any computer based program can have errors - the old garbage in, garbage out adage applies.

You don't program the spreadsheet and go. You run a lot of different scenarios. Ones that will not cause issues and ones that you know before you even enter the numbers would never work. You then compare all that against the POH or AFM. You get comfortable enough that you know it will work when properly used.
+TSRA is offline  
Old 10th Mar 2016, 15:11
  #7 (permalink)  
 
Join Date: Jan 2003
Location: Manchester
Age: 41
Posts: 596
I've used a company approved. specialist spreadsheet on the 74F. But could still do a manual L/S (never ever used), but it meant I could spot an error, as someone previously said GIGO.
Ex Cargo Clown 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 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.