14 CFR § 93.226

If there are available slots in the following time periods and there are no pending requests for international or EAS operations at these times, FAA will allocate slots upon request on a first-come, first-served basis, as set forth in this section:

Any period for which a slot is available less than 5 days per week.

Any time period for which a slot is available for less than a full season.

For LaGuardia and Washington National Airports:

6:00 a.m.-6:59 a.m.

10:00 p.m.-midnight.

Slots will be allocated only to operators with the economic and operating authority and aircraft required to use the slots.

Requests for allocations under this section shall be submitted in writing to the address listed in § 93.221(a)(1) and shall identify the request as made under this section.

The FAA may deny requests made under this section after a determination that all remaining slots in a particular category should be distributed by lottery.

Slots may be allocated on a seasonal or temporary basis under this provision.