Aviation finance has lived with the airframe and engines split for forty years. The lessor owns the metal, the operator maintains it to contractual return conditions, and hours-on-wing decide what the asset is worth at redelivery. That same discipline is now being asked of space, and the question is whether it ports.
Why Ireland already runs this playbook
Irish lessors manage 9,504 of the world's 14,678 leased aircraft, 64% by number, on Aircraft Leasing Ireland figures published by Ibec on 12/11/2025. AerCap, Avolon, SMBC Aviation Capital and a long tail of smaller lessors sit inside a cluster that grew out of Tony Ryan's GPA in the 1970s and never left. Industry estimates put the global aircraft-leasing market north of €350bn in asset value, and a large share of it is structured, booked or tax-resident in Ireland.
That did not happen by accident. It rests on three things: a deep bench of people who can model residual values and write lease documentation, an extensive double-tax treaty network, and Section 110 of the Taxes Consolidation Act 1997, which lets a qualifying special-purpose company hold and finance assets on a tax-neutral basis. The same machinery that books a narrowbody on a twelve-year operating lease can book a ground station or a satellite.
What maps cleanly
The mechanics of aircraft leasing translate to space infrastructure more directly than most people expect.
| Aviation | Space equivalent |
|---|---|
| Airframe / engine split | Spacecraft bus / payload split |
| Operating vs finance lease | Same distinction under IFRS 16 |
| Hours-on-wing, cycles | Transponder-hours, station-keeping fuel, design life |
| Return conditions at redelivery | End-of-life and de-orbit obligations |
| Residual-value modelling | Harder, but the method holds |
| Operator credit assessment | Identical underwriting question |
Ground segment is where the analogy is strongest. A teleport or ground station is a fixed asset with a long economic life, a definable maintenance regime, and a creditworthy operator paying to use it. That is a sale-leaseback waiting to happen.
The financing structure ports without modification. A finance lease transfers the risks and rewards of ownership to the lessee; an operating lease keeps residual exposure with the lessor. IFRS 16 applies the same way whether the asset flies at 11,000 metres or sits in a field in Cork. The S.110 SPV that holds it does not care what the asset does for a living.
Where it breaks
Honesty about the limits is the point of the exercise.
You cannot repossess an on-orbit asset. The entire enforcement logic of aircraft leasing rests on the lessor's ability to take the aircraft back, and the Cape Town Convention exists precisely to make cross-border repossession fast and predictable. There is no equivalent for a satellite in geostationary orbit. Once it is up, security has to be taken over the cash flows, the operating company, and the ground infrastructure, not the spacecraft itself.
The aircraft you can always fly home. The satellite you cannot. Everything in the credit structure follows from that one fact.
Title is also messier. An aircraft has a clean registration and a single owner. A satellite's value is bound up with spectrum rights and orbital slots coordinated through the ITU, which are licensed to operators, not owned by lessors, and do not transfer with the hardware. And the secondary market is thin. There are hundreds of buyers for a used A320; there is no liquid market for a used satellite, which makes residual-value modelling far more conservative and pushes most early deals toward ground assets and finance-lease structures where residual risk is contained.
The natural home for it
Put the two halves together. The asset class needs people who can underwrite long-duration infrastructure against operator credit, document leases that survive a default, and hold the asset in a tax-neutral, treaty-covered vehicle. Ireland has spent fifty years building exactly that capability for aircraft, and the institutional knowledge is portable in a way the spacecraft are not.
Caelum is built on that overlap: aviation and maritime structured-finance discipline, one Section 110 DAC per deal and EU domicile. It finances both halves of the system: satellites, acquired at in-orbit delivery or already in service, and the ground stations that control them. On the ground the security is conventional. In orbit it sits in the lease, the revenue contracts and the ground-control arrangements.
Sources
IBA, Global Aircraft Leasing Market Outlook (fleet values and lessor share). Cirium Fleet Analyzer, leased-fleet management data by jurisdiction. Convention on International Interests in Mobile Equipment (Cape Town Convention, 2001) and the Aircraft Protocol. PwC Ireland, Aviation Finance sector reporting on the Irish leasing cluster. Irish Revenue, Guidance on Section 110 Companies (Taxes Consolidation Act 1997).