America's toothless Tiger Moth, the F‑35, has copped another backhander from US government auditors: the US Government Accountability Office reckons its logistics software isn't ready for battlefield deployment.

The GAO also warns that the US$16.7bn Autonomic Logistics Information System (ALIS) could, instead, swallow anything between $20 and $100bn.

Those warnings are contained in a report (PDF) titled DoD Needs a Plan to Address Risks Related to Its Central Logistics System.

The GAO is also concerned that the DoD's management of ALIS is so ad-hoc that the "full scale production" due-date of 2019 might not be met.

The two most serious issues with ALIS that the GAO highlights are:

Deployability – Since ALIS requires connectivity to a server, the software might not be deployable to the "austere" locations where the US Marine Corp operates. The Marines told the GAO that's okay, because the F‑35s can run missions without ALIS.

Since ALIS requires connectivity to a server, the software might not be deployable to the "austere" locations where the US Marine Corp operates. The Marines told the GAO that's okay, because the F‑35s can run missions without ALIS. Redundancy – The GAO says ALIS has "no backup system or redundancy"; all data uses a single point of entry. A failure "could take the entire F‑35 fleet offline."

Redundancy should, however, arrive in 2017, when backup hardware now on order is delivered and commissioned.

There's also this criticism: "By continuing to respond to issues on a case-by-case basis rather than in a holistic manner, there is no guarantee that DOD will address the highest risks by the start of full-rate production in 2019, and as a result, DOD may encounter further schedule and development delays, which could affect operations and potentially lead to cost increases."

The risk of delay arises because ALIS's logistical role goes beyond being the spare-parts tracker for the F‑35. As the Project on Government Oversight puts it, ALIS is meant to "diagnose mechanical problems, order and track replacement parts, and guide maintenance crews through repairs. It also allows pilots to plan missions and later review their performance."

Without ALIS, the fleet would eventually grind to a halt, although Defense One quotes US Air Force F‑35 program chief Lt Gen Chris Bogdan as saying the fleet can operate without it for 30 days.

The F‑35's dependency on software has plagued the system recently. In March, the US House Armed Services Committee was warned dodgy software could result in the aircraft missing its 2019 full-scale production date, and earlier this year, it emerged that the best way to keep the radar operational in flight was to turn it off and turn it back on again. ®