Space-A
Eligibility
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Who Qualifies for Space-A Travel?
Space-Available (Space-A) travel is a benefit that allows eligible military personnel, dependents, and retirees to fly on U.S. military aircraft when seats are not needed for duty passengers. Eligibility and boarding priority are governed by AMC Instruction 36-3802 and administered by Air Mobility Command (AMC) passenger terminals worldwide.
All Space-A travel is on a non-interference basis — mission requirements and duty passengers always come first. Travelers are placed into one of six priority categories (Cat I through Cat VI) based on their military status, leave type, and deployment situation. Within each category, boarding priority is determined by signup date and time.
For the authoritative source, visit the official AMC Travel site at amc.af.mil.
The Six Space-A Categories
AMC assigns every Space-A traveler to one of six categories. Higher-numbered categories board only after all lower-numbered categories have been accommodated. Understanding your category is the single most important step in planning a Space-A trip.
Category I — Emergency Leave
Highest priority. Category I is reserved for active duty service members who are traveling on emergency leave due to a documented family emergency — such as the death or critical illness of an immediate family member. An American Red Cross emergency message is typically required to establish the emergency. Cat I travelers can board even after the roll call has closed, making this the most expedited form of Space-A travel available.
Documents typically required: Leave orders, Red Cross emergency message, military ID.
Category II — Environmental and Morale Leave (EML)
Second priority. Category II applies to active duty service members, DoD civilian employees (GS), and DoDDS/DoDEA teachers stationed at certain OCONUS locations who are traveling on Environmental and Morale Leave (EML) orders. A critical requirement: the sponsor must accompany the dependents. The entire family unit must travel together for Cat II eligibility — unaccompanied dependents on EML fall under Cat IV.
Documents typically required: EML orders, military ID or DoD civilian ID, dependent IDs or passports.
Category III — Active Duty on Ordinary Leave
Third priority. Category III is the most common Space-A category. It covers active duty service members traveling on approved ordinary leave. Leave must be documented on a DA Form 31 (Army) or AF Form 988 (Air Force), or the equivalent for other branches. Leave dates must be current and valid for the duration of travel.
Category III also covers a specific dependent situation: unaccompanied dependents of service members deployed for 365 or more consecutive days. These dependents travel without the sponsor and carry a commander-signed authorization letter verifying the deployment length.
Documents typically required: Signed leave form (DA 31/AF 988), military ID, dependent IDs.
Category IV — Unaccompanied Dependents (EML & Deployed 30–364 Days)
Fourth priority. Category IV covers two groups of unaccompanied dependents:
EML dependents:Dependents of overseas-based service members traveling unaccompanied on EML. Maximum two trips annually, excluded from the first and last six months of the sponsor's tour. Must register within 6 hours at transit locations.
Deployed sponsor dependents (30–364 days): Dependents of service members deployed 30–364 consecutive days can travel anywhere worldwide where Space-A seats are available, repeatedly throughout the deployment. They need a Deployed Sponsor Dependent Verification Letter (valid for entire deployment). Can register up to 10 days before the deployment begins.
The deployment threshold that separates Cat IV from Cat III is 365 consecutive days. Dependents of members deployed 365+ days qualify for the higher Cat III (ranked lowest within that category).
Documents typically required: Deployed Sponsor Dependent Verification Letter, sponsor's deployment orders, dependent IDs.
Category V — Unaccompanied Dependents
Fifth priority. Category V covers unaccompanied dependents of active duty members who do not qualify for the EML-based Cat IV:
Command-sponsored dependents stationed OCONUS with their sponsor can fly unaccompanied with a commander authorization memo. This includes dependents at unaccompanied tour locations like Korea, Greenland, and other remote assignments— they can fly Cat V on a commander's memo even though the sponsor's tour is unaccompanied.
Cat V also includes students (ROTC cadets, service academy, NUPOC) and personnel on non-housing permissive TDY.
Note: Reserve and National Guard members who are not on active duty orders are Category VI, not Category V.
Documents typically required: Commander authorization letter (memo), dependent ID (DD Form 1173), student enrollment verification (if applicable).
Category VI — Retired Military, P&T Disabled Veterans, and Others
Lowest priority. Category VI is the broadest category with different travel restrictions depending on your sub-group:
Retirees receiving retirement pay can fly Space-A anywhere seats are available — worldwide, including international routes to Europe, the Pacific, and all OCONUS destinations. This is the key distinction: retirees with pay are NOT restricted to CONUS.
100% Permanent & Total (P&T) disabled veterans with a DOD ID card (DD-2765) can fly Space-A but are restricted to CONUS and US territories (Alaska, Hawaii, Puerto Rico, USVI, Guam, American Samoa). International flights to foreign countries are not authorized. Note: 100% service-connected without the P&T designation does not qualify — you must be rated P&T and have obtained a DOD ID card through DEERS.
Cat VI also includes Gray Area retirees (Reserve/Guard members with 20+ qualifying years not yet drawing pay) who are eligible for CONUS + US territories travel, drilling Guard/Reserve members (same CONUS + territories restriction), and surviving spouses of deceased service members (contiguous US only — the most restrictive travel area in Cat VI).
Documents typically required: Retiree ID (DD Form 2 Retired) + passport for international travel; DOD ID card (DD-2765) + VA Benefits Summary Letter for P&T veterans; DD-2765 or NOE letter for gray area retirees.
How Boarding Priority Works
Understanding the category system is only half the equation. Within each category, the terminal boards travelers in signup date and time order — first in, first out. Here is how the process works in practice:
Signup Rules by Category
Active duty members cannot sign up for Space-A until their leave has started. Your signup date is the date your leave begins — you cannot register in advance of your leave start date. This is a common misconception.
For retirees, P&T disabled veterans, gray area retirees, and drilling Guard/Reserve, you can register up to 60 days before your desired travel date. Your signup timestamp locks in your position within your category — the earlier you sign up, the higher your seniority within Cat VI.
Signup is typically done via email to the passenger terminal. You can sign up at multiple terminals simultaneously. Signups are valid for 60 days before being purged.
Roll Call and Manifesting
When a flight becomes available, the terminal conducts a roll call. Travelers are called by category, then by signup date/time within the category. If you are present and answer the roll call, you are eligible to board (space permitting). If you miss your name at roll call, you may be skipped — so stay close to the terminal when a flight is expected.
Multi-Terminal Strategy
Experienced Space-A travelers register at several terminals along possible routing paths. Since signup lists are terminal-specific, registering early at multiple locations gives you more opportunities to catch a flight and a stronger position at each terminal.
Frequently Asked Questions
Can retirees fly Space-A internationally?
Yes. Retired military members receiving retirement pay can fly Space-A anywhere seats are available — including international routes to Europe, the Pacific, and all OCONUS destinations worldwide. The CONUS-only restriction within Cat VI applies to P&T disabled veterans, gray area retirees, and drilling Guard/Reserve — not to retirees drawing retirement pay.
Can Reserve or National Guard members fly Space-A to Europe?
No. Reserve and National Guard members who are not on active duty orders travel under Category VI and are restricted to CONUS and US territories only — international flights to foreign countries are not authorized. Once a Reserve or Guard member is activated on Title 10 orders, they travel as active duty (Cat III on leave) and can fly internationally.
Do dependents need the sponsor present to fly Space-A?
It depends on the category. For Category II (EML), yes — the active duty sponsor must be present and accompany the dependents; unaccompanied EML travel for dependents at Cat II is not permitted. For Category III (dependents of 365+ day deployments), Category IV (unaccompanied EML dependents), and Category V dependents, the sponsor does not need to be present — but specific documentation such as commander authorization letters is required.
How long is a Space-A signup valid?
A Space-A signup is valid for 60 days from the date and time you registered. Your position within your category is determined by that original signup timestamp. If your plans change or your leave is extended, you may need to re-register, which will reset your signup date and move you to the back of the line within your category.
What is the difference between Cat III and Cat IV for deployed dependents?
The threshold is 365 consecutive days of deployment. If the active duty sponsor is deployed for 365 or more consecutive days, their unaccompanied dependents qualify for the higher-priority Category III. If the deployment is between 30 and 364 consecutive days, the unaccompanied dependents fall under Category IV, which carries a lower boarding priority and requires a commander authorization letter. In both cases, dependents travel without the sponsor and must carry appropriate documentation.
Who are Gray Area retirees and do they qualify for Space-A?
Gray Area retirees are Reserve Component members (Army Reserve, Navy Reserve, Marine Corps Reserve, Air Force Reserve, Coast Guard Reserve, or National Guard) who have completed 20+ qualifying years of service but have not yet begun drawing retirement pay. Per recent NDAA changes, Gray Area retirees are now eligible for Space-A travel under Category VI. They are restricted to CONUS and US territories (no international flights to foreign countries). Once a Gray Area retiree begins drawing retirement pay, their restriction lifts and they gain worldwide Space-A travel access like other pay-eligible retirees.
Disclaimer
Space-A Central is an unofficial, independent tool built to help military travelers plan their trips. The information on this page is provided for general educational purposes only and may not reflect the most current AMC policies, terminal procedures, or regulatory changes.
Always verify your eligibility, required documentation, and current terminal procedures directly with the AMC passenger terminal you plan to use and through official sources including AMC's official travel site. The governing regulation for Space-A travel is AMC Instruction 36-3802 (Space-Available Travel). Space-A Central is not affiliated with, endorsed by, or sponsored by the U.S. Department of Defense, Air Mobility Command, or any branch of the U.S. Armed Forces.