Aircraft Weight and Balance Records Requirements: What the FAA Requires You to Keep

Last reviewed June 16, 2026 · By Chad Griffith

<p>Aircraft weight and balance records fall into two distinct types. The aircraft's <strong>master weight and balance record</strong> is the running document of empty weight and center of gravity, updated whenever equipment changes (14 CFR 43.9) and retained with the aircraft. The per-flight <strong>load manifest</strong> is a separate record that Part 135 multiengine operators must prepare for each takeoff and keep for at least 30 days (14 CFR 135.63(c)).</p>

What weight and balance records does the FAA require?

The FAA requires three layers of weight and balance documentation, and operators routinely confuse them. Knowing which record answers which rule is the difference between a clean inspection and a finding.

1. The aircraft's master weight and balance record. Every aircraft has an established empty weight and center of gravity (CG). The original values come from the type certificate and Airplane Flight Manual (AFM); thereafter the record is amended whenever installed equipment changes. This record is retained with the aircraft's permanent records.
2. The per-flight load manifest. Under 14 CFR 135.63(c), a Part 135 certificate holder must prepare a load manifest in duplicate before each takeoff in a multiengine aircraft. This is an operational record, prepared fresh for every flight, and retained for at least 30 days.
3. The currency / reweigh record. Under 14 CFR 135.185(a), the current empty weight and CG of a multiengine Part 135 aircraft must be calculated from values established by actual weighing within the preceding 36 calendar months (with limited exceptions). The weighing record is the proof the master record is still current.

In plain terms: the master record says what the empty aircraft weighs, the reweigh record proves that figure is still valid, and the load manifest proves each individual flight was loaded within limits.

Where the weight and balance data must live: the aircraft and the AFM

Weight and balance limits are not optional reference material. They originate at type certification and must travel with the aircraft.

Under the airworthiness standards, the established weight and CG limits are furnished in the Airplane Flight Manual. For transport-category airplanes, 14 CFR 25.1583(c) states the weight and CG limitations must be furnished in the AFM (or in a separate weight and balance document incorporated by reference). For normal-category airplanes certificated under the part 23 performance-based rules, 14 CFR 23.2620 requires the AFM to contain operating limitations and loading information.

Once the aircraft is in service, 14 CFR 91.9(b) requires that a current, approved Airplane or Rotorcraft Flight Manual (and the approved manual material that carries the weight and balance data) be available in the aircraft. The takeaway: the W&B data the crew computes against must be the current, approved data, and it must be accessible during operations — not buried in a file at the operations base.

The Part 135 load manifest: contents, who carries it, and the 30-day rule

This is the record most often cited in a Part 135 records review, and it has the most specific requirements. Under 14 CFR 135.63(c), the certificate holder is responsible for preparing a load manifest in duplicate before each takeoff for multiengine aircraft. The manifest must contain:

• The number of passengers
• The total weight of the loaded aircraft
• The maximum allowable takeoff weight for that flight
• The center of gravity limits
• The center of gravity of the loaded aircraft (or a notation that it is within limits when determined by an approved method)
• The registration number of the aircraft or the flight number
• The origin and destination
• Identification of crew members and their crew position assignments

Who carries it: the pilot in command of an aircraft for which a load manifest must be prepared must carry a copy of the completed load manifest in the aircraft to its destination.

Retention: the certificate holder must keep copies of completed load manifests for at least 30 days at its principal operations base, or at another approved location.

The 30-day window is the trap. The load manifest is an everyday operational document, easy to generate and just as easy to misplace, so a records audit that pulls a flight from three weeks ago expects to find the matching completed manifest on file. A missing or incomplete manifest for a flight inside that window is a discrete, citable gap.

Empty weight currency: the 36-calendar-month reweigh rule (135.185)

An empty-weight figure does not stay valid forever. Under 14 CFR 135.185(a), no person may operate a multiengine aircraft under Part 135 unless the current empty weight and center of gravity are calculated from values established by actual weighing of the aircraft within the preceding 36 calendar months.

14 CFR 135.185(b) provides two exceptions. The reweigh requirement does not apply to: (1) an aircraft issued an original airworthiness certificate within the preceding 36 calendar months, or (2) an aircraft operated under a weight and balance system approved in the certificate holder's operations specifications (a fleet weight-control program).

For records purposes, the reweigh date is the anchor. If the aircraft is not on an approved fleet W&B program, the dated weighing record is what proves compliance, and it expires on a rolling 36-month clock. Treat it like any other expiring compliance artifact: know the date, know when it lapses, and have the next weighing scheduled before it does.

Recording weight and balance changes from equipment changes and alterations (43.9)

The master weight and balance record is only correct if every change that moves the empty weight or CG is captured. When equipment is installed, removed, or relocated, or when an alteration is performed, the work generates a maintenance record under 14 CFR 43.9(a), which requires an entry containing a description of (or reference to data for) the work performed, the date of completion, the name of the person performing the work, and the signature, certificate number, and kind of certificate held by the person approving the aircraft for return to service.

For major alterations, 14 CFR 43.9(d) directs that the work be recorded on the form and in the manner prescribed by the FAA (FAA Form 337, Major Repair and Alteration), which captures the resulting change to weight and balance. The revised empty weight, CG, and useful load are then carried forward into the aircraft's master weight and balance record. The chain only holds if the alteration record, the Form 337 where applicable, and the updated master W&B figures all agree — a reviewer cross-checks them against each other.

Keeping weight and balance records inspection-ready with FileFlo

FileFlo is a compliance document-intelligence platform — the records and proof layer, not a weight and balance calculator, a dispatch system, or a maintenance-tracking system. It does not compute your CG or build your load sheet. It makes sure the records that prove your compliance are classified, current, complete, and exportable on demand.

When you upload a document, FileFlo classifies it to its governing CFR citation — a completed load manifest, a weighing record, a Form 337, an AFM revision — and tracks the dates that matter. It flags the rolling 36-month reweigh window from 14 CFR 135.185 before it lapses, surfaces load manifests so you can confirm the 30-day file under 14 CFR 135.63 is intact, and flags records that are missing entirely. When an inspector or auditor asks, FileFlo exports an organized, inspection-ready audit binder with each document mapped to the rule it satisfies.

FileFlo is $89 or $299 per month with a 5-day free trial. (FileFlo is not SOC 2 certified.) The standard caveat applies: FileFlo organizes and surfaces your records — the operator remains responsible for the accuracy of every weight and balance computation and for actual regulatory compliance.

Master weight and balance record vs. load manifest: don't conflate them

These two records answer different questions and follow different rules. Mixing them up is the most common weight and balance recordkeeping error in Part 135 operations.

A clean records review confirms both: a current, properly amended master record backed by an in-date weighing, and a complete 30-day file of load manifests, each loaded within the limits the master record establishes.

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