Space-A Scout › Routes › MCAS Iwakuni to Seattle-Tacoma Intl
MCAS Iwakuni sent 45 recorded Space-A flights to Seattle-Tacoma Intl in the year ending October 2026, about once a week and about 12 percent of everything the terminal flew. On the 44 of those where the terminal reported who made the cut, Category VI travelers, the retirees and veterans at the back of the line, got a seat 32 percent of the time.
By raw volume, September and August saw the most departures on this route in the year ending October 2026, and November the fewest. The route was active in 13 of the 13 months on record.
Saturday is the day to watch: 36 of the 45 roll calls for this route, 80 percent, fell on a Saturday.
Category VI is the last group called at roll call. On this route, 32 percent of the 44 reported flights still had room by the time Cat VI was called. This is one of the tougher routes for retirees, so flexibility and a backup plan matter more here than most places.
The lowest category that made each reported flight, in the year ending October 2026:
| Category II | 2 flights |
| Category III | 8 flights |
| Category IV | 15 flights |
| Category V | 5 flights |
| Category VI | 14 flights |
Seats are the other half of the picture. On the 45 flights that reported both numbers, the terminal released an average of 16 seats and 5 were taken, so a typical flight on this route left with about 11 Space-A seats empty. Some room most days, but not so much that showing up late is safe.
A schedule on the 72-hour board is a plan, not a promise, and on this route the record says how much of a plan. Of the 18 flights posted to MCAS Iwakuni's board for Seattle-Tacoma Intl in the last 120 days, 2 (11 percent) disappeared from the board more than twelve hours before they were due to fly, 0 (0 percent) changed their roll-call time after first posting, and 0 (0 percent) changed their seat count. Normal turbulence for Space-A. Check the board the night before and again the morning of.
Sign-up at MCAS Iwakuni is free and does not commit you to anything. You can email the terminal at M_IWKN_SMBIwakuniSpa@usmc.mil (the email doubles as your dated proof of sign-up), use the AMC online sign-up portal and call 011-81-827-79-5509 to confirm anything time-sensitive. Do it 45 to 60 days before you want to travel, because your place in line at roll call is your sign-up date, and a sign-up is good for 60 days.
In the year ending October 2026, MCAS Iwakuni recorded 45 Space-A flights to Seattle-Tacoma Intl, which works out to about once a week. Firm schedules only appear about 72 hours ahead; the free live boards at spaceascout.com show what is posted now.
In the year ending October 2026, Category VI travelers, which covers retirees and eligible veterans, made the cut on 32 percent of the 44 flights where MCAS Iwakuni reported a category for this route.
Email M_IWKN_SMBIwakuniSpa@usmc.mil with your name, category, number of travelers and desired destinations, or use the AMC online portal. Sign up 45 to 60 days before you want to fly. It is free and the email gives you a dated record.
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Open the live boards for MCAS Iwakuni
Space-A Scout collects 72-hour schedules, Patriot Express calendars and roll-call results from more than a hundred passenger terminals, refreshed every twenty minutes. It is free and no account is required. Built by Luke Connally, USMC, Retired, who flies Space-A himself. See every route we hold records for, every base, or start with the five-minute primer.