The F-35 was supposed to be down to 1 percent of maintenance actions.
After seeing some mid-2000s trouble with the F-22 in IOC, this assumption changed to 2 percent.
These numbers aren't as valid if the part/component life rating of the item in the 1-2 percent group isn't all that good and needs frequent replacement.
In the case of the F-22, it offers real combat value.
Not so with the F-35.

All part of a bigger maintenance picture for the F-35 in regard to materials used.
This from what I blogged in 2009.
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