All 6 Space-A categories at a glance
Category I — Emergency Leave Unfunded Travel
Active-duty members and family on Red-Cross-verified emergency leave
Priority: Highest
Category II — Sponsored Environmental and Morale Leave (EML)
Active-duty members and family stationed at qualifying EML-designated overseas duty stations, traveling on sponsored EML orders
Priority: Very High
Category III — Ordinary Leave, R&R, House Hunting PTDY, Medal of Honor Holders, Foreign Cadets
Active-duty members on chargeable leave (ordinary) and accompanying family. Members on R&R from a combat zone. Members on permissive TDY for house hunting (limited). Medal of Honor recipients (with family). Foreign cadets at U.S. service academies.
Priority: High
Category IV — Unaccompanied Dependents on EML / DoDDS Teachers
Family members traveling on EML without their sponsor. DoD Education Activity (DoDEA / DoDDS) teachers traveling during winter and summer break.
Priority: Medium-High
Category V — Permissive TDY (Non-EML), Students
Members on permissive TDY (other than house-hunting). Students who are dependents of active duty traveling for education-related reasons. Members on convalescent leave (post-medical).
Priority: Medium-Low
Category VI — Retirees, Reservists w/ 20-year Letter, 100% Disabled Veterans, Surviving Spouses, Foreign Gov Sponsored
Retired members (regular Title 10 + Reserve gray-area at age 60+) and their accompanying family. Reservists with their 20-year letter (gray-area, pre-pay). Veterans with a permanent service-connected disability rated as total, and their dependents when accompanied by the veteran (Table 3 item 47 — CONUS, and directly between CONUS and Alaska, Hawaii, Puerto Rico, the U.S. Virgin Islands, Guam and American Samoa). Surviving spouses of Service members who died on active duty, in inactive duty training or annual training status, and of retired members, with their accompanying dependents (Table 3 items 48–51 — CONUS only). Foreign government sponsored travel.
Priority: Lowest
How Space-A actually works
Space-Available (Space-A) is the program by which the Air Mobility Command (AMC) and other DoD operators offer unused seats on military aircraft — primarily KC-135s, C-17s, C-5s, C-130s, and Patriot Express commercial-charter flights — to eligible passengers. The premise is simple: if a plane is flying anyway and seats are empty, fill them.
Cost: Most flights are free. Patriot Express and certain contract flights charge a head tax (typically $20.00–$40.00 per leg). In-flight meals on some C-5 or commercial-charter legs cost $5.00–$15.00 cash. There are no booked reservations and no refunds — you sign up, you show up, and you go if a seat clears.
The category priority rule
The 6 categories form a strict priority queue. Every flight clears Category I passengers first, then Category II, then III, then IV, then V, then VI — until seats run out. Within a single category, passengers clear in first-in, first-out order based on sign-up date/time, NOT travel date.
Practical implication: Sign up the moment you have leave approved (at most 60 days in advance for CONUS/short-haul; longer windows for OCONUS). A retiree (Category VI) who signs up 60 days early can clear ahead of a retiree who signs up 1 day early IF no higher-category passengers compete for the same seats.
Sign-up methods (3 ways)
- AMC online portal: Visit amc.af.mil/AMC-Travel/Space-A-Travel and submit Form AMC 140 up to 60 days in advance of travel. Your sign-up time stamps when AMC receives the form.
- In-person at passenger terminal: Walk into the Space-A passenger terminal at your departure base (Andrews JBA, Travis AFB, McGuire JB-MDL, Hickam JBPHH, Ramstein, Yokota, Kadena, etc.) and sign up at the desk. Sign-up time stamps when the terminal logs you.
- Email/fax: Many bases accept Form AMC 140 via email to the terminal's published address. Sign-up time stamps when the email arrives (NOT when you sent it — internet delays can move you down the list).
Show time: Once at the terminal, you must show up for "roll call" (typically 2–3 hours before flight) to be marked present and eligible for that flight. Miss roll call = no seat that day. Your sign-up date is still good for the next flight, though.
Documentation checklist
- Photo ID: CAC for active duty; military ID for family; retiree ID for retirees. ALL passengers (including infants) must have valid ID.
- Travel authority: Leave form (active duty), retiree ID (retirees), or EML orders.
- Passport + visa: Required for nearly all OCONUS destinations. Tourist passport works for retirees; active-duty members and their families generally use a no-fee passport (must be applied for via installation passport office). Some countries require visa in addition.
- Vaccination records: A few destinations still require yellow card or specific vaccines.
- Cash: $50.00–$100.00 for head tax, in-flight meals, and lodging at destination if your hop is delayed.
Tips that actually work
- Have flexible dates and multiple destination options. Listing "Anywhere" on your sign-up doubles your chances vs. listing a specific country.
- Check the flight schedule daily. AMC posts "72-hour" and "30-day" schedules at terminals and on the AMC mobile app. Patterns emerge — certain routes fly every Tuesday/Thursday, others are sporadic.
- Avoid peak holiday weeks. Mid-December and mid-June see massive Category VI volume (retiree travel) that can stretch waits to 5+ days even at major hubs.
- Sign up at multiple terminals. If you're flexible, sign up at Norfolk, Charleston, Travis, and Hickam simultaneously. Higher chance one terminal clears your category.
- Use Patriot Express (commercial charter): AMC contracts Patriot Express on routes from CONUS to OCONUS (Germany, Japan, Korea, Guam, Bahrain). PE flights are commercial 767s with usually 30+ Space-A seats per flight, making them more reliable than C-17/C-5 missions.
- Travel light and have backup lodging: If your Space-A hop returns empty, you may be stranded at the destination. Have a Plan B (commercial booking on points, billeting reservation, etc.).
Common confusions clarified
- "Can I bring my civilian friend?" No. Only the listed eligible persons in DoDI 4515.13 Table 3 may fly Space-A. Civilians can occasionally accompany under specific Foreign Government Sponsorship or DoDEA teacher rules but not as "+1 of a member."
- "Can my Reserve sponsor bring family without me?" Reservists with a 20-year letter (gray-area) and their FAMILY can fly Space-A — but the Reservist must be present on the hop. Family-without-sponsor is not authorized for gray-area Reservists.
- "Do I need orders for ordinary leave Space-A?" Yes — a valid leave form (paper or DTS) is required. "Permissive Leave" or "Day Pass" is not sufficient.
- "Can I check bags?" Yes — up to 2 bags at 70 lb each per traveler (varies by aircraft). C-17 / C-5 missions sometimes allow heavier baggage including pets in cabin. PE flights follow commercial 50-lb rules.
- "Are pets allowed?" On most AMC flights, yes — in approved kennels in the cargo hold. Patriot Express accepts pet shipping for a fee. Service animals fly in cabin. Pet policies vary by aircraft type and route; always verify with the terminal.