Generally the statute of limitattions for a non capital offense in Federal Court is 5 years. That means the charges need to be filed within that time.If the person skipped bond after being arrested but prior to being formally charged, the clock is stopped until the person is arrested on the warrant. If the person was already charged within 5 years of the alleged act and then skipped bond, the statute of limitations is satisfied since the law won't allow a fugitive from justice to benefit by secreting themself to avoid prosecution.
Generally, the SOL would be 5 years, but keep in mind that a failure to appear, skipping bond, etc. will toll that time period and allow the government to bring these charges even after 5 years has passed.
I agree with the answers of both other counsel, that the act of being charged and processed, with the 'skipping' occurring after the person was put on bail (bond) acts to toll (stay) the SOL. It's not that there is no SOL, the SOL clock is stopped because of the act of the person charged.
I suggest you discuss this case and this particular issue with an experienced criminal defense lawyer admitted in NY Federal Court.