Mass & Balance

Set up an aircraft Mass & Balance profile and calculate, sign and print a loadsheet for each flight

Flylogs calculates a Mass & Balance loadsheet for each flight. Enter who and what is aboard and the fuel. Flylogs then works out the zero fuel, ramp, take-off and landing mass and centre of gravity (CG). It checks them against the aircraft's limits and plots them on the CG envelope.

Each aircraft needs a Mass & Balance profile before its flights can have a loadsheet.

Flylogs does the arithmetic, but the pilot in command stays responsible for loading the aircraft. Every figure in the profile must come from this aircraft's approved flight manual (AFM/POH, section 6) and its latest weighing report.

The aircraft profile

Open the aircraft and find the Mass & Balance card, under Certificates & expirations. Click Set up, or Edit if a profile already exists.

The Mass & Balance card on the aircraft page

A profile contains:

Section	What to enter
Units	Mass in kg or lb; arm in m, mm, cm or in. Use the units of the flight manual. Changing a unit does not convert values already entered.
Weighing	Basic empty mass and its arm, weighing date and weighing report reference.
Limits	Max take-off mass (required), max landing, max zero fuel and max ramp mass (optional).
Loading stations	One row per seat row, baggage area or fuel tank, each with its arm from the AFM loading table. Seats and baggage can have a maximum mass. Fuel tanks have a fuel unit (litres, US or imperial gallons), a density, and an optional usable capacity. The AVGAS and Jet A-1 buttons fill a typical density; check it against your AFM.
CG envelope	The forward and aft limits as mass / arm points, exactly as the AFM or type certificate gives them. Between points the limit is a straight line. Below the first point and above the last it stays constant.
Landing envelope	Optional, for aircraft whose landing CG limits differ from take-off. It only adds limits: the landing CG is checked against the landing envelope and the normal envelope, so you can enter it as a simple box without copying the normal envelope's sloped lines.

The preview chart updates as you type. Before saving you must tick the box confirming you checked every value against the flight manual and weighing report.

The profile editor: template, weighing and limits, loading stations and CG envelope

Type templates

To save typing, choose a type template. Templates for your aircraft model are listed first. A template fills in the units, maximum masses, envelope and whatever loading stations the public data gives. It never fills in the basic empty mass or arm.

Templates exist for common types such as the Cessna 150/152/172/206/210/208, Piper PA-28-181, PA-34 Seneca V and PA-38, Diamond DA40 / DA40 NG / DA42 / DA62, Tecnam P2008 / P92 / P-Mentor, Cirrus SR20/SR22, TBM 700 N and Pilatus PC-12/47E. They come from public type certificate data sheets and, where noted, AFM pages. Each template names its source and lists what to check: serial number ranges, modifications that change the limits, and stations you still need to add.

A template is a starting point, not a certified profile. Many types have several envelopes depending on serial number or installed modifications (for example the DA40 NG maximum take-off mass of 1280 or 1310 kg). Always compare it with your own flight manual.

Not covered: helicopters (they need a lateral CG check), aircraft whose limits are only given in % MAC, and airliners or business jets (use your operator's loadsheet system).

Who can edit the profile

Action	Who
View the profile	Everyone in the company
Create, edit or delete it	Flylogs Administrator, Company Administrator, Operations Manager, Compliance & Safety Manager, Chief Pilot, Mechanic — and the private owner of the aircraft

Deleting a profile does not change loadsheets already saved on flights: each keeps its own copy.

The flight loadsheet

On a flight with an aircraft that has a profile, the Loadsheet card appears in the right-hand column. Click Calculate loadsheet (or Open loadsheet once one exists).

The Loadsheet card on the flight page

1. For each seat and baggage station, enter the mass. For seats, pick who sits there from a searchable list of the flight's crew, the passengers on the manifest and the company's users; a seat row can hold several people. For baggage, optionally type what is loaded. A new loadsheet puts the PIC (CM1) and the SIC (CM2, or the supervisor when there is no SIC) on the first seat row and spreads the manifest passengers over the other seats. Masses are always left for you to enter.

2. For each fuel tank enter volumes:

   • Ramp: fuel on board at engine start.

   • Taxi: fuel burnt before take-off. Take-off fuel is ramp minus taxi.

   • Trip: fuel burnt before landing.

3. The Result panel shows the zero fuel, ramp, take-off and landing mass and CG against the maximums, a list of every limit exceeded, and the points on the envelope chart.

4. Click Save. The server recalculates the loadsheet with the aircraft's current profile and stores it with the flight, including a copy of the profile used.

The loadsheet: what is loaded on the left, the result and the envelope on the right

The loadsheet checks:

• each station's maximum mass and each tank's usable capacity,

• taxi fuel not greater than ramp fuel, and trip fuel not greater than take-off fuel,

• max zero fuel, ramp, take-off and landing mass,

• CG inside the envelope at zero fuel, take-off and landing. When there is a landing envelope, the landing CG must be inside both the landing envelope and the normal envelope. The chart draws the landing envelope clipped to the normal one, so the dashed line never goes outside it.

Signing

Once a loadsheet is saved within limits, the PIC (or the flight's supervisor) can Sign it by entering their password. The signature records who, when and from which device. It is bound to the exact numbers saved.

• Changing any figure and saving again removes the signature.

• A loadsheet outside limits cannot be signed.

• If the aircraft or its profile changes after saving, the loadsheet is marked as out of date. Save it again to recalculate before signing.

• If the stored numbers no longer match the signature, Flylogs shows the signature as invalid.

PDF

PDF prints the saved loadsheet: flight details, loading table, results, exceeded limits, the envelope chart, who calculated it and who signed it. Save your changes first; the PDF always shows the stored loadsheet, not unsaved screen values.

Who can use loadsheets

Action	Who
View	Anyone who can view the flight. Captains, pilots, students, cabin crew and specialists (groups above Flight Instructor, below Auditor) only for flights they are on or aircraft they own
Calculate, save or delete	The flight's creator, PIC, SIC or supervisor; any of the aircraft's managers; Flylogs Administrator, Company Administrator, Operations Manager, Compliance & Safety Manager, Flight Dispatcher, Chief Pilot and Flight Instructor. Not on cancelled or deleted flights
Sign	The PIC or the supervisor only (the creator if the flight has no PIC)

Auditors, cabin crew and specialists can read loadsheets but not change them.

See also the Mass & Balance API.