Kevin,
It sounds like they are paying you on an hourly basis (Non-Exempt), but are arranging your schedule to avoid paying you overtime. It may make scheduling easier for the Government, and You may like that situation, however it may violate the way the Federal Government defines how all Government employee's are supposed to be paid.
An employer can define overtime as any time over 8 hours per day. They can also say overtime is any time over 40 hours per week or any time over 80 hours in 2 weeks. So if you work 10 hours one day but you do not work more than 40 hours that week, then you are not eligable for 2 hours overtime pay for the one day you worked 10 hours.
I think the government has problems scheduling you for a flat 8 hour day or even a 10 hour day since airline schedules change and there are many flight delays due to weather, etc. I know since I was a road warrior (consultant) and would put on about 100K air miles in 6 months.
As for class action suits? I have been envolved in about 3 of them. The last one was about 7-8 years ago involving the way State Farm Insurance in Texas handled and paid Uninsured Motoris accidents. After over nine months of filling out claim forms and even going to Dallas to testify before a panel of 3 judges and about 10 lawyers, I got nothing.
Even though the documents indicated that State Farm was required to pay a minimum of $5000 property damage for each accident involving an unisured motorist, and even more if there were injuries sustained in the accident. My claim involved my daughter who got rearended by uninsured Mexican national (he had a legal green card) Her neck was injured and State Farm only paid the initial $2500 for no-fault PIP (Personal Injury Protection) and my daughter stopped going to the Doctory because State Farm said it would not pay for anymore treatments.
Personally, if you have no complaints about how you are paid, I would not give $100 to those blood sucking lawyers. I don't think they can sue the federal government in a class action suit a federal judge will not have the federal government put up the money to pay for the attorney fees, that's why they want you to pay them up front, and nothing is likely to happen so they won't get any more money.
...Rich