Splitting an aircraft among partners is the most common way to have access to an airplane or helicopter without bearing the hangar, insurance, maintenance and crew alone. The math makes sense on paper. What usually goes wrong is living together: who flew more, who left the tank empty, who pays for the inspection that came due in the month nobody flew.
This guide separates the two things. First, what the regulations say about an aircraft with several owners. Then, how to organize the operation so that the split is a report, not an argument.
Two different formats
Co-ownership
The most common format is the condominium: the aircraft is registered in the Brazilian Aeronautical Registry (RAB) in the name of two or more people, each with their share. The registry keeps each owner's percentage. Acts concerning the aircraft require everyone's participation: ANAC Resolution No. 293/2013 requires, for aircraft owned in condominium, the signatures of all owners on the form (art. 56, § 1), and the Brazilian Aeronautical Code (CBA) only allows a mortgage on a jointly owned aircraft with the express consent of all co-owners (art. 140).
Shared ownership program
RBAC 91 has a subpart of its own for a more structured model: Subpart K, operations of aircraft under shared ownership. It is not for just any co-ownership. The program brings together two or more airworthy aircraft (91.1001(b)(5)) under a program manager, and the minimum share is 1/16 of a fixed-wing aircraft and 1/32 of a rotary-wing aircraft (91.1001(b)(10)).
Two rules define the model:
- Operational control always belongs to the manager, who is listed as the operator of the aircraft in the RAB, even when the flight is made for the benefit of a co-owner (91.1009(a)).
- Carriage of persons or property for compensation is prohibited on a program flight, except for the reimbursements provided for in 91.501 (91.1005(a)).
The manager also has obligations of its own in the subpart, such as management specifications, a manual and an SMS (SGSO). For two or three friends with a single aircraft, Subpart K is not the way; for a company that wants to sell shares in a fleet, it is.
Who the operator is
The question seems bureaucratic and is not: the operator answers for the aircraft. The Brazilian Aeronautical Code defines the operator as whoever uses the aircraft, their own or someone else's (art. 123). When there is an operator (explorador) registered in the RAB, the owner is excluded from that liability; without registration, the owner is deemed the operator until proven otherwise, and operator and owner are jointly liable (art. 124).
In co-ownership, it is worth defining in the contract and in the registry who the operator is, and not leaving the answer for the day someone needs it.
Splitting costs is not selling flights
Co-owners split costs. What they cannot do is turn the share into a transport service: charging a third party for the seat, or charging the other co-owner an "hour" with a margin, is operating an air service, which requires certification. The Brazilian Aeronautical Code treats operating any air service without observing the authority's regulations as an infraction (art. 302, III, "f"), and ANAC runs a campaign against clandestine air transport, in which the company and the pilot can be held liable.
For large airplanes and turbine-powered multiengine airplanes, RBAC 91 describes the joint ownership agreement: one of the registered owners employs and provides the crew, and the others share the total costs as set in the agreement (91.501(c)(3)). Outside that universe, the reference is the same: the split covers cost, without profit, among those who own the aircraft.
What usually causes fights, and how to avoid it
In practice, conflicts among co-owners repeat themselves. Almost all of them come from data that nobody recorded at the time.
Schedule. Two co-owners want the aircraft on the same holiday. A single schedule, with a written rule on priority and advance notice, avoids the last-minute conversation.
Hours flown. If each flight does not record whose leg it was, the end of the month turns into rebuilding from memory. The logbook needs to say who flew and on whose account.
Fuel. One co-owner refuels, flies half the tank and the next one flies with the fuel the first one paid for. Without recording who paid for each refueling and how much each flight consumed, there is no way to settle up.
Fixed and variable costs. Hangar, insurance and calendar-based maintenance keep running even with the aircraft on the ground; fuel, fees and wear depend on who flies. The contract should say how each type is split, and the records need to separate the two.
Maintenance coming due. The hour-based inspection comes due on one co-owner's flight, but it was produced by everyone's hours. It is worth agreeing on a maintenance reserve fed by the hours flown, instead of catching whoever had the aircraft that day.
A co-owner leaving. The contract needs to provide for how the share is valued, who has the right of first refusal and what happens to the outstanding balance of expenses.
None of these points has a regulatory solution: it is contract and records. The regulations only require that the aircraft be operated and maintained like any other, with the logbook and maintenance records up to date.
Where Alis fits in
Alis has features designed for an aircraft with more than one owner, which work on top of the same flight recorded in the logbook:
- Co-owners registered per aircraft, with an invitation link for each one to complete their own registration, without needing a login to be listed.
- Single schedule, in which the co-owner can request, reschedule or cancel their flight, also through WhatsApp, and the other co-owners are notified.
- Owner of each leg on the flight and a report of hours flown by owner.
- Expenses per aircraft with a split among the responsible parties marked, and a report with the split by owner or co-owner.
- Fuel account per co-owner: the credit is what each one paid for refueling, the debit is the consumption of the flights in which they were the owner of the leg (measured or estimated from the aircraft's average consumption), and the balance comes out in liters and in reais at the period's average price, as a PDF for settling up.
- ANAC-accepted electronic logbook and maintenance tracking counted down with every flight, so that due dates belong to everyone and are in view of everyone.
Expense splitting in Alis is done equally among the responsible parties marked on each entry. Anyone who splits fixed costs by share percentage still does that calculation outside the system.
See the plans for private and shared aircraft on the aircraft page.
This article is for informational purposes and was written based on RBAC 91 (Amendment No. 08), the Brazilian Aeronautical Code (Law No. 7.565/1986, as amended by Law No. 14.368/2022) and ANAC Resolution No. 293/2013, as published and read in November 2026. It does not replace consulting the regulations or legal advice on the contract among co-owners.