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I'm a student participating in a design project wherein we have to develop a paper design for a payload to be airdropped from a C-130J. Naturally, I'd like to look at the weight and balance of the C-130 to see what sort of limitations we have (since we'd like to literally fill the cargo bay with multiples of this payload), but it does not seem to be available anywhere. I found a CNI-MU emulator on Google Play that gives some basic information (basic weight/arm, crew weight/arm, fuel weight/arm), and I have a loadmaster form from the 2015 Defense Transport Regulations that shows me the cargo hold layout. However, something's not lining up.

The default information loaded into the emulator places the basic weight at STA 730 and the fuel at STA 750, which is roughly where the aircraft ramp begins according to the DTR cabin layout (which labels it as corresponding to the B/E/H models, but, according to the DTR, it applies to the J model as well), but it seems strange because, according to the CNI-MU emulator, that's around the quarter-chord of the wing, which is a little behind the center of the cargo hold.

In other words, I'm a bit confused and am looking for anyone who might be able to either make sense of the above or answer the following question:

What is the loading diagram for a C-130J (i.e., what is the basic weight/arm, crew arm, fuel arm, and payload stations within the cargo cabin)?

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  • $\begingroup$ Hi Marius. Welcome to Aviation.SE. I'm sorry to say that I have voted to close your question. I think it's a good question but needs very specific expertise to accurately answer. I am fairly certain that you will not find that expertise here. $\endgroup$ – Simon Apr 30 '16 at 17:28
  • $\begingroup$ Why don't you ask where the load should be relative to the wing? This way you don't need the specific C-130 J diagrams but gain knowledge which can be applied to all aircraft. $\endgroup$ – Peter Kämpf Apr 30 '16 at 17:54
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    $\begingroup$ I respectfully disagree with @Simon. I believe it to be a reasonable question. The difficulty is locating the basic information. If you really want to understand what's going on, you need not only that mentioned in your last sentence in bold but the monocoque limits, the linear limits, the lateral imbalance limits, as well as whatever might be unique to C-130 weight and balance. What you need is the equivalent for the C-130 to what you will find for the 747 at terryliittschwager.com/wbmanuals.php. $\endgroup$ – Terry Apr 30 '16 at 21:14
  • $\begingroup$ @PeterKämpf -- agreed: the important thing is the placement of the aircraft CG. However, given my past experience in aircraft, I figure that this is generally located in front of the quarter-chord...but, in order to load this particular aircraft such that that occurs, I need the weight and balance information for the aircraft, as mentioned by Terry. $\endgroup$ – Marius May 1 '16 at 23:58
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    $\begingroup$ I would agree with @Terry. Just because we don't currently have the expertise at the site to answer the question doesn't mean it should be closed (we're not in beta anymore! :). Some day, a C130 load master might just stop by and answer this. Probably too late for the OP, but it will be nice to have the answer somewhere on the interwebz. $\endgroup$ – FreeMan May 2 '16 at 17:26
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As listed on a CNI-MU emulator designed for use by C-130J loadmasters, the following is a list loads and moment arms for the aircraft:

  • Basic weight: 80,000 lbf/STA 530
  • Crew weight: 600 lbf/STA 153
  • Fuel weight: 38,000 lbf/STA 551 -- this weight is, naturally, variable, although the moment arm appears to stay relatively constant.

  • CG limits: 21-30% MAC

Finally, payload moment arms can be determined via use of of DD form 2130-2 on page III-V-17 of the 2015 Defense Transport Regulations (http://www.ustranscom.mil/dtr/part-iii/dtr_part_iii_app_v.pdf).

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    $\begingroup$ Congrats on finding it, and thanks for coming back to post! $\endgroup$ – FreeMan May 4 '16 at 16:00
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Sorry I saw this late. I am a C-130J Loadmaster and teach the course to Air Force students. I am on my mobile, but can answer more later. For a quick answer though, you are mixing up two variants of the -J. The -30 is a stretch, and those are the numbers you found. Flight station 737 is at the ramp on a short model. The -30 is 200" longer however. The mean aerodynamic chord of c-130 any variant or model is 164.5". Leading edge to MAC of a stubble is 487.4". -30 LEMAC is 687.4"

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