
The legislation that enabled the transfer of seven C-130H aircraft from the Coast Guard to the U.S. Forest Service to serve as air tankers required that the wing boxes be replaced and other maintenance be performed.
A wing box is the core or backbone of an aircraft. In a C-130 it sits atop the fuselage and forms the attachment point for both wings. A failure of the wing box during flight could be catastrophic.
In the mid-2000s, center wing boxes (CWB) on C-130s began showing cracks earlier than expected. Many of the aircraft were grounded or placed on restricted flight status, including some that were flying in Iraq and Afghanistan. In 2006 the Air Force began a program to replace them on all C-130 models except the C-130J which entered the inventory in February, 1999. By 2020, 155 C-130s will have new CWBs that are the same ones being manufactured today for the C-130J.

The total cost of a CWB kit in 2011 was $6.7 million, including installation which takes about 10 months.

A couple of years ago the Coast Guard identified six C-130Hs to undergo CWB replacements. The first, #1706 seen in the photo above, was completed August 12, 2012. A second C-130 began the process in November, 2012 and should have been complete by September, 2013. The other six aircraft numbers that are being transferred to the USFS are 1708, 1709, 1713, 1714, 1719, and 1721. Many of the CWB replacements for the Air Force and Coast Guard aircraft are being done at Robins Air Force Base in Georgia.
The Coast Guard expected that the CWB and other upgrades would allow the C-130Hs to serve until 2027, after which they would be replaced by new aircraft. They have already started ordering C-130Js, tagging on to Air Force procurement programs..
Wildfire Today has found information which indicates the seven C-130s being given away by the Coast Guard were manufactured between 1983 and 1987, but this is not yet confirmed. If the data is accurate, they are 27 to 31 years old now, and will be 40 to 44 years old in 2017. A person might wonder why the Coast Guard can buy new C-130Js while the U.S. Forest Service has to make do with hand-me-down aircraft being discarded by another agency.

In addition to replacing the CWBs, the legislation requires “progressive fuselage structural inspections” for the seven Coast Guard C-130s being transferred to the USFS. If they receive the standard primary structure inspection — known as programmed depot maintenance — that process will take between 180 and 200 days. In February, 2013, the Ogden Air Logistic Complex at Hill Air Force Base in Utah began performing some of the programmed depot maintenance on the Coast Guard C-130s, aircraft which are similar to the C-130s flown by the Air Force, but they have more avionics for radios and radar.
The legislation directed that no more than $130 million be spent by the Department of Defense to modify and maintain the seven C-130s before the transfer; any additional funds would have to come from the USFS. Doing a little math here, if the CWB replacement costs $7 million each, the programmed depot maintenance runs $3 million per aircraft (to pick a number out of the air), and the installation of the retardant tank system is $4 million (Coulson’s preliminary estimate is $3.5 million each for their Aero Union/Coulson RADS tank), we are looking at a total of about $98 million — within the $130 maximum allowed by Congress. If $14 million is subtracted for CWB replacements that have already occurred on two aircraft, that total is brought down to $84 million.
However, there will no doubt be other work that will have to be done to the aircraft, such as installation of radios, a real time location tracking system, and perhaps other avionics and a stress monitoring system. It is also possible that unneeded equipment such as a cargo handling system and armor will have to be removed, all of which could require more USFS dollars unless these items are included in the total conversion project funded by the military, rather than done later by the USFS. These additional tasks would push the price closer to the $130 million threshold.





