Dual Licence B1+B2 Logbook Tracking Explained

Holding both B1 and B2 privileges on the same aircraft type is common — and logging it correctly is where most digital and paper logbooks alike start to break down. This guide covers what a dual-licence entry actually means, how it should count toward your recency on both sides, and the mistakes that quietly cost engineers currency they've genuinely earned.

What "dual licence" actually means

A B1/B2 dual licence means you're endorsed under both categories on a given aircraft type — commonly written as B1.1+B2, B1.3+B2, and so on. It's not a separate licence category of its own; it's two sets of privileges (mechanical under B1, avionics/electrical under B2) held simultaneously on the same type rating.

This matters for logbook purposes because B1 and B2 have entirely separate recency clocks under 66.A.20(b)(2), even when they're endorsed on the same aircraft type for the same person. Your B1 currency and your B2 currency on that type are tracked independently — one can lapse while the other stays current.

The task that counts for both

Here's the part that trips people up: a single maintenance task, correctly documented, can legitimately count toward both recency clocks — but only if it was genuinely performed under both sets of privileges, not just because you happen to hold both licences.

A worked example: you troubleshoot and rectify a wiring fault that also required removing and refitting a mechanical panel to gain access. If your task record and supervisor's certification reflect work under both B1 and B2 privileges for that job, it's legitimate to log it as a dual-category entry — and it should be counted toward both your B1 and B2 100-day/180-task tallies for that aircraft type.

What's not legitimate: logging every task as B1+B2 by default because it's quicker, regardless of what was actually done. Authorities and quality departments do check for this pattern — a logbook where every single entry is dual-tagged, with no pure B1 or pure B2 entries at all, tends to draw scrutiny rather than avoid it.

Why most logbooks handle this badly

Paper logbooks and generic spreadsheets typically have one "category" column. Faced with a dual-privilege task, engineers either:

Pick one category and lose the day/task credit on the other side entirely, or
Write "B1+B2" as a single combined string, which then needs manual splitting every time someone calculates recency — a step that's easy to skip or get wrong, especially under deadline pressure before a licence renewal.

Neither is good. The first quietly erodes your recorded experience. The second works until someone (an auditor, a new employer's quality department, or you six months from now) needs to actually calculate two separate 24-month rolling windows from a pile of combined-category text entries by hand.

What correct dual-licence tracking looks like

A properly built system should treat a dual-privilege task as generating credit toward two independent recency records — same date, same aircraft type, two category tallies — without you having to enter the task twice or do the arithmetic yourself. Concretely, that means:

One entry, two category fields. The task is logged once, with both the primary and additional licence category captured explicitly (not squeezed into a single free-text field).
Separate recency cards per category. Your Experience or currency view should show a B1 card and a B2 card for that aircraft type, each with its own distinct-days count, task count, and 6-month spread check — not one blended number that obscures which side is actually current.
Letters that reflect both. A Recency Letter or Experience Letter generated for authority submission or a new employer should list both categories against the type, with each one's status (current, building, or lapsed) shown separately.

A related trap: Category C

If you also hold Category C (base maintenance certifying staff) alongside B1/B2, don't assume it slots into the same recency model. Category C doesn't follow the 100-day/180-task/6-month-spread structure the same way — it's a task tally against your organisation's procedures, not a rolling currency clock. A system that tries to force Category C into the same B1/B2 recency logic will give you a number that looks precise and means very little. Keep it tracked, but keep it separate.

Practical checklist for dual-licence entries

Only tag a task as dual-category if both sets of privileges were genuinely exercised and the certification reflects that
Make sure your logbook tool captures the second category as its own field, not appended text
Check that your Experience view shows independent B1 and B2 status per aircraft type — if it only shows one blended figure, you can't actually verify your own currency at a glance
Before a licence renewal, authorisation renewal, or job application, generate separate letters (or a letter with both categories clearly broken out) rather than relying on a single combined summary

Tracking it without the manual arithmetic

This is precisely the gap AirMXTrack was built to close for dual-licence engineers. Log a task once, tag it with both B1.1 and B2 (or whichever combination applies), and it counts toward both recency clocks automatically — with independent Experience cards, independent status, and Recency Letters that show both categories clearly, per aircraft type.

Track dual-licence recency automatically → airmxtrack.com

AirMXTrack is a digital maintenance logbook built by a Licensed Aircraft Engineer, for Licensed Aircraft Engineers. Free to start, no credit card required.