Four pilots. One PA-28. Split four ways, the numbers suddenly make ownership viable. Then someone misses a maintenance payment, two owners argue over who gets the aircraft for a bank holiday weekend, and the annual is overdue because nobody was clearly responsible for booking it.
This scenario plays out constantly across European flying groups. The aircraft economics work. The operational structure was never written down.
This article covers the practical and legal basics of aircraft co-ownership in Europe: how to structure it, what a shared aircraft ownership agreement needs to include, who carries maintenance responsibility, and what tends to go wrong when you skip the groundwork. It is not legal or financial advice — for anything that touches your specific jurisdiction, tax position, or liability exposure, get a qualified professional involved.
Ownership Structure Options
Before you draft any agreement, you need to decide how the aircraft will be owned. There are three common approaches in European GA.
Joint ownership (undivided shares) All co-owners appear on the aircraft registration as joint owners. Each person holds a fractional interest in the whole aircraft — not a specific part of it. This is the simplest structure and works well for small groups (two to four people). In most EASA member states, the registration authority will accept joint ownership if you follow their specific process. Check with your national aviation authority (NAA) — requirements vary between, say, the CAA in the UK (now post-EASA), the LBA in Germany, or ANAC in France.
Association or club structure A small informal association or unincorporated club holds the aircraft. Members buy shares in the association rather than the aircraft directly. This adds a layer of separation but also adds administrative overhead. Some groups use this to make it easier to sell or transfer shares without re-registering the aircraft.
Limited company (SRL, GmbH, Ltd, etc.) The aircraft is owned by a company, and the co-owners hold shares in the company. This can offer liability protection and makes share transfers cleaner on paper. It also means annual accounts, a registered address, and corporate administration — costs that can exceed the savings for a four-seat touring aircraft. It's more commonly used for higher-value aircraft or larger groups.
Which structure fits depends on the number of owners, the aircraft value, your jurisdiction, and how much administration you're willing to carry. A solicitor or notary familiar with aviation assets in your country is worth a short consultation before you commit.
What a Co-Ownership Agreement Must Cover
A handshake is not an agreement. Neither is a WhatsApp message that says "we'll split everything four ways." A written shared aircraft ownership agreement is the document that prevents most of the disputes that end co-ownerships badly.
At minimum, it should address:
- Ownership percentages and capital contributions. Who paid what, and what percentage does each owner hold. If one person contributed more to the purchase, does that translate to more flight hours or just more equity?
- Scheduling and priority. How do owners book the aircraft? What's the booking window? What happens when two owners want the same slot? Is there a tie-break rule (first to book, rotating priority, etc.)?
- Monthly fixed costs. Hangarage, insurance, annual inspection, and any loan repayments are shared regardless of how much anyone flies. Define the split and the payment schedule. Define what happens if someone doesn't pay.
- Variable costs. Fuel, oil, and landing fees are usually paid by the person who flew. Decide whether engine reserve contributions are fixed per hour or per owner per month.
- Maintenance decisions. Who is the nominated maintenance contact? Who approves unscheduled work above a threshold amount (say, €500)? What happens if owners disagree on a repair?
- Airworthiness responsibility. Under EASA rules, a non-commercially operated aircraft not managed by a CAMO can be maintained under Part-M Subpart C by the owner. If there are multiple owners, the agreement should name one person as the point of contact for maintenance coordination. This is not a regulatory designation — it's an internal operational decision — but it matters enormously in practice.
- Insurance. Who arranges it? What hull value? What liability limits? Are all owners named? What's the process if a claim is made?
- Permitted users. Can owners bring non-owner pilots? If so, what are the minimum licence and currency requirements? Who is responsible if a non-owner damages the aircraft?
- Selling a share. What is the process if an owner wants to exit? Is there a right of first refusal for existing owners? How is the share valued?
- Dissolution. If the group decides to sell the aircraft, how is that decision made and how are proceeds distributed?
None of this is exotic. All of it causes arguments when it's not written down.
Maintenance Responsibility Under EASA
For a privately operated aircraft on an EASA member state register, the owner is responsible for ensuring the aircraft is maintained in an airworthy condition. When there are multiple owners, that responsibility doesn't divide neatly.
For most light GA aircraft, the applicable framework is EASA Part-M. The aircraft needs an approved Maintenance Programme, and continuing airworthiness management can either be contracted to a CAMO (Continuing Airworthiness Management Organisation) or, for certain aircraft categories, handled directly by the owner under Part-M Subpart C. Check your aircraft category — ELA1 and ELA2 aircraft have specific provisions.
In practice, most small co-ownership groups contract a local Part-145 approved maintenance organisation or a suitably qualified independent certifying staff member to do the scheduled and unscheduled work, and one co-owner acts as the de facto maintenance coordinator. That person chases the 50-hour and annual checks, monitors the ADs, and escalates to the group when decisions are needed.
If you're buying into an existing group, ask to see the current maintenance records, the ARC (Airworthiness Review Certificate) status, and any open squawks before you sign anything.
What Actually Breaks Down Operationally
The failure modes in aircraft co-ownership are almost always predictable. Here's what comes up repeatedly.
Scheduling conflicts without a system. Four owners with flexible schedules and one aircraft. If booking is done by text message or email, someone will get the aircraft they expected and someone won't. The solution is a shared calendar with clear booking rules — not goodwill.
Unequal use creating resentment. One owner flies 80 hours a year. Another flies 12. If fixed costs are split equally, the low-utilisation owner is subsidising the high-utilisation owner's hobby. Some groups handle this with minimum hour commitments or adjusted cost splits. Either way, it needs to be explicit.
Deferred maintenance because nobody owns the decision. When an unscheduled squawk comes in — a rough mag, a leaking brake — and there's no named decision-maker, it sits. The aircraft gets flown anyway. This is how airworthiness deteriorates in group-owned aircraft.
Exits handled badly. An owner wants to sell their share. There's no agreed valuation method. One owner thinks the share is worth €8,000. Another thinks €5,000. Without a pre-agreed mechanism (independent appraisal, book value formula, right of first refusal at a stated price), this can freeze the group for months.
Insurance gaps. A non-owner pilot, brought along by one of the owners, has an incident. The policy only covers named pilots. The group is now having a conversation nobody wanted to have.
None of these are hypothetical edge cases. They're the standard failure modes. A well-drafted agreement and a functioning scheduling system prevent most of them.
Practical Next Steps Before You Buy In
If you're evaluating a share in an existing group, or setting one up from scratch, work through this list before money changes hands:
- Confirm the ownership structure and how your name (or entity) appears on the registration.
- Review or draft a written co-ownership agreement covering the items listed above.
- Check the maintenance records, ARC validity, and any open MEL items or deferred squawks.
- Confirm the insurance policy covers your intended use, your licence type, and any non-owner pilots you plan to bring.
- Agree on a scheduling system before the first conflict, not after.
- Name one person as maintenance coordinator and one as the financial administrator — even if it rotates annually.
For scheduling and cost-sharing within a group, Planebooker handles aircraft availability, booking conflict detection, and billing — including prepaid wallets and split payment tracking — which is a reasonable fit for a co-ownership group that wants to stop running ops through a group chat. It's worth a look once your agreement is in place and you know what you actually need to track.