The Trade

Sky Harbour is building private hangars for large-cabin business jets at supply-constrained US airports. The thesis is that airport land is finite, modern jets are physically too large for legacy hangars, and the first mover capturing ground leases at the best airports will earn REIT-like pricing power without REIT-like competition.

The Q4 2025 earnings call (filed March 19, three days ago) confirmed this with hard data: 22% re-leasing markups on completed transactions in Miami and Nashville, on top of existing CPI escalators. Not guidance. Not a model. Signed leases, cash deposited, tenants locked in at 22% above their prior rent.

Nobody is modeling this because nobody covers the stock. Zero analysts. $700M market cap. SPAC origin. The stock is down 22% over the past year while the fundamental story is the strongest it has ever been.

The trade is a probability bet. The market implies ≈11% chance of the bull case materializing. We estimate 25%. That 14-point edge on the probability, expressed through a hedged common position or a small warrant sidecar, is the trade.

Why This Exists

The Physics

Business jets are getting taller. The G700 needs 25'5" clearance. The Global 7500 needs 27'. The Falcon 10X, which rolled out in Bordeaux on March 10, stands 29 feet tall. It will not fit in any standard legacy hangar in the United States.

45% of existing US hangar stock was built in the 1970s and 80s with 20-24 foot doors. This isn't a demand forecast or a management claim — AGP Aviation, an independent hangar developer, cites the same statistic. NBAA sources repeat it. The physical dimensions of the aircraft and the physical dimensions of the doors are both measurable. They don't agree. This doesn't reverse.

The Demand

854 business jets were delivered in 2025, up 11.8% from 764. Record $35.7 billion in billings. These numbers come from GAMA's official report — SKYH's CEO cited them on the call and they match exactly.

Every major OEM confirms the picture independently:

• Gulfstream (GD): 158 deliveries (+16%), backlog $21.8B, book-to-bill 1.4x, guiding 160+ in 2026
• Bombardier: 86 large-cabin deliveries (+18%), backlog $17.5B (+22%), first Global 8000
• Textron: $6B aviation revenue (+13%), backlog $7.7B
• Dassault: 37 Falcons (+19%), Falcon 10X in flight testing

65% of new deliveries are large-cabin — the segment that doesn't fit in legacy hangars is the segment growing fastest.

The caveat on growth: OEMs guide mid-single-digit delivery growth for 2026, not the double-digit pace of 2025. Bombardier flagged "brutal" engine supply constraints. The secular trend is real — the fleet is physically getting bigger — but the delivery growth rate normalizes from here. The hangar thesis doesn't need delivery acceleration. It needs the existing fleet and new deliveries to keep trending toward larger airframes, which is structural (G700, G800, Global 8000, Falcon 10X are all in production or entering service). A 5% delivery growth rate with 65% large-cabin mix creates the same hangar obsolescence pressure as a 12% rate — just more slowly.

The Supply Constraint

You cannot build more airport land. This is the simplest supply thesis in real estate. Airports are fixed assets. Runway-adjacent parcels are finite. Ground leases take 2-3 years to negotiate and entitle. There is no zoning variance that creates a new ramp at Opa-Locka or Teterboro.

SKYH has secured ground leases at 23 airports covering 4.16 million square feet of buildable hangar space. They currently operate 1.1 million. The pipeline is 4x current operations, fully funded ($48M cash + $150M subordinate bonds + $200M JP Morgan facility). No equity raise required.

The Pricing Power — With an Asterisk

The 22% re-leasing markup is the cornerstone evidence, but it needs honest framing.

In Miami and Nashville, leases that expired in 2025 were renewed at 22% above the last year of the prior lease. On top of that, the new leases carry 4% CPI floors (up from 3%). Management themselves tempered expectations: "We do not expect 22% to persist indefinitely... even 5-11% would be a very exciting story."

The catch-up question: We don't know the base rents on those expired leases. If they were signed during COVID at below-market rates, the 22% step-up is partly catch-up to current market, not pure supply-driven pricing power. Management didn't break this out. The 10-K (filed March 19, not yet reviewed) might clarify this — it's an open question.

The REIT comparison cuts both ways. The best supply-constrained industrial REITs achieve comparable spreads: EastGroup Properties reported 19-25% cash re-leasing in 2025. Terreno Realty hit 22.6%. But Rexford Industrial — the cautionary comp — saw SoCal market rents drop 20% from 2023 peak when supply caught up and macro softened. Occupancy fell to 90.2%. Even "infill" markets can overbuild. Airport land is qualitatively more constrained than any industrial submarket (you can rezone a warehouse site; you cannot rezone a runway), but the REXR example is a reminder that pricing power is partly cyclical, not purely structural.

The sustainable number matters more than the headline. If SKYH can sustain 10-15% re-leasing spreads (management said 5-11% would be "very exciting"), that compounds dramatically over 30-year ground leases. The thesis doesn't need 22% to persist. It needs supply-constrained airports to price like supply-constrained airports — which the REIT comps suggest they do. But the magnitude may be more modest than the Q4 headline implies.

Pre-construction campuses are preleasing at $44.85 per square foot, above the $40 target. These are hard leases with cash deposits for hangars that haven't been built yet. Dallas International, where SKYH doesn't even have a permit, already has signed tenants. This is harder to explain away as catch-up — new tenants at new campuses are signing above-model rents voluntarily.

The Vehicle Problem

Here's what makes this harder than the thesis suggests.

Beta: 1.49. Idiosyncratic variance: 38.8%. Our thesis is 100% company-specific. But only 39% of the stock's variance is company-specific. Going long SKYH unhedged is 60% a bet on SPY and 40% a bet on hangar pricing power. If the S&P drops 10%, SKYH drops ≈15% regardless of whether Miami Phase 2 opens on time.

The factor decomposition:

Total edge: ≈50%. Below the 75% target. This means either hedge the beta or accept that more than half your P&L is market noise.

The stock trades as a SPAC. It should trade as a specialty REIT. That reclassification — from "pre-profitability de-SPAC" to "infrastructure compounder" — is itself a latent factor. When EBITDA turns clearly positive and management provides NOI guidance (committed for Q1 2026 call), REIT analysts may discover it. Beta drops, idio variance rises, valuation multiples shift from revenue to cap rate. That transition is a 50% probability event within 12 months.

The Capital Structure — What the Bonds Actually Say

The $150M subordinate bond issuance (Series 2026) deserves scrutiny beyond "3x oversubscribed."

What's genuinely positive: Tax-exempt at 6% fixed, underwritten by Barclays and JPMorgan, 18 institutional investors. These aren't retail bagholders — institutional muni buyers did their own credit work on an UNRATED security and still oversubscribed 3x. That's a real signal about the underlying asset quality.

What's genuinely concerning: Capitalized interest through January 2029. That means no debt service payments for three years. The projects being built with this money must be generating cash flow by then, or the structure stresses. If construction delays cascade or lease-up is slower than expected, the cushion evaporates. The 5-year mandatory tender (January 2031) creates refinancing risk — if rates are higher or credit has deteriorated, the takeout could be expensive or unavailable.

The ROE claim is management's model. "Same campus goes from 30% ROE to 60%+ ROE" — this depends on construction costs hitting target (<$250/sq ft), lease-up speed matching plan (6-9 months to stabilization), and refinancing terms being favorable. All three have execution risk. The first-vintage campuses already came in above cost target (COVID inflation + a design issue that required additional equity injection). The model works in a spreadsheet. Whether it works in the field is what the next 12 months will tell us.

Scenarios

Bull Case: 25% probability, target $22.67 (+140%)

Everything executes. Miami Phase 2 opens on time (late April). Q2 2026 EBITDA is clearly positive (May 12 earnings). Management provides NOI guidance that lets the market model the business. Bradley CT opens in September (first NYC-area campus). An analyst initiates coverage. The stock reclassifies from SPAC to specialty REIT in investor minds. Re-leasing markups settle at 10-15%. The 4x pipeline starts being valued as future NOI, not as capex risk.

Base Case: 45% probability, target $11.07 (+17%)

SKYH executes but the re-rating takes longer than expected. Miami Phase 2 opens with minor slippage. EBITDA turns positive but modestly. Revenue reaches $45-55M in 2026. Leasing team scales but remains a mild constraint. No analyst initiation. Competition rumblings stay anecdotal. The stock grinds from $9.45 to $11 range by year-end — not enough for the warrant to have value, but the common earns a modest return.

Bear Case: 30% probability, target $2.96 (-69%)

Construction delays cascade. Leasing team can't scale fast enough. First-vintage IRR disappoints when published — the COVID cost overruns and design issue translate into sub-threshold returns even after higher rents. A PE-backed competitor captures ground leases at key airports. Macro deterioration reduces BizAv utilization. The sub bonds' capitalized interest period ends in 2029 with insufficient cash flow to service them. Warrant expires worthless. Common re-rates to distressed developer.

Scenario EV: $11.54 (+22% from $9.45)

What the Market Gets Wrong

The current price ($9.45) implies ≈11% probability of the bull case. We estimate 25%. The 14-point edge comes from three things the market hasn't processed:

1. The re-leasing data is three days old and nobody reads the transcript. Even if 22% is partly COVID catch-up, the preleasing data at $44.85/sq ft on pre-construction campuses is not catch-up. New tenants at new airports are signing hard leases with cash deposits at 12% above the $40 target. That signal has zero catch-up contamination — it's pure forward pricing power.

2. The demand corroboration is unusually deep. Four independent OEMs confirming record backlogs and growing large-cabin deliveries is not standard for a micro-cap thesis. Most small-cap theses rely on management claims. This one has GD, Bombardier, Textron, and Dassault independently validating the same demand picture. GAMA's official data matches the CEO's numbers exactly. The 45% obsolescence figure appears in third-party industry sources. The evidence quality exceeds what most covered stocks produce. The growth rate normalizes from here (mid-single-digit OEM guidance for 2026), but the LEVEL of demand and the SIZE trend are structural and confirmed.

3. The dilution bear case was surgically removed. $150M sub bonds (3x oversubscribed, 18 institutional investors, Barclays/JPM underwritten) replace dilutive equity. The liquidity "fortress" ($398M total) funds the pipeline to 2M square feet. The persistent fear with SPACs — "they'll dilute you to fund growth" — was addressed in February. The stock hasn't reacted because nobody noticed. Whether the bonds create their own risks (2029 capitalized interest cliff, 2031 refinancing) is a separate question — but the equity dilution thesis, which is what the market was pricing, has changed.

What Could Kill This

First-vintage IRR. Management admitted yield-on-cost was below target on the earliest campuses (COVID construction inflation + a design issue that required additional equity injection). They promised to publish vintage IRRs when the obligated group completes. If those numbers show sub-threshold returns even after accounting for higher rents, the unit economics model is weaker than the illustration suggests. This is the biggest unresolved bear test.

The COVID catch-up question on re-leasing. If the 22% turns out to be predominantly catch-up from below-market COVID leases rather than structural supply premium, the re-leasing thesis weakens. Management's own words — "we don't expect 22% to persist" — could mean they know this. The preleasing data at $44.85 on new campuses is the cleaner signal, but it's a smaller sample.

Leasing team bottleneck. The CEO admitted they're "stretched a little thin" and "a little bit behind the eight ball" on leasing. When you're about to 4x your footprint, your leasing bottleneck is your revenue bottleneck. Denver is already leasing up slower than expected (seasonal, per management). If the pattern repeats at non-Sunbelt campuses, the 6-9 month stabilization timeline is optimistic.

The 2029 interest cliff. Sub-bond capitalized interest ends January 2029. The projects funded by these bonds must be generating cash by then. If construction slips materially or lease-up is slow, SKYH faces debt service on projects that aren't yet cash-flowing. This isn't a near-term risk (3 years out) but it's the structural risk embedded in the "fortress of liquidity" narrative.

The warrant's fuse. SKYH-WT: $11.50 strike, January 25, 2027 expiry. 10 months. Common needs +22% to reach intrinsic value, +30% to break even at expiration. The catalyst sequence (April/May) gives two shots. If neither fires, the warrant goes to zero. 15.8M warrants outstanding — if they expire worthless, that's $181M of potential equity capital that never materializes.

Competition. For the first time on any call, the CEO acknowledged "rumblings of competition." He preempted the question — volunteered it before an analyst asked. That's a CEO who sees something specific. Our corroboration found no direct competitor replicating the home-base model — Vantage (Jadian PE) is FBO, Sheltair is FBO/MRO, Atlantic and Signature (Blackstone) are transient operations. But PE capital is circling aviation infrastructure. The land-capture moat measured in years of entitlement work is the defense. The risk is that PE firms recognize the HBO opportunity and pivot, or that airport authorities develop their own facilities. Neither has materialized in public data, but the window is narrowing.

Market beta. With beta at 1.49, a 15% SPY drawdown wipes 22% off SKYH. The thesis can be right and you still lose on timing. Hedge the beta or accept the noise.

Sizing

Current price vs fair value: The stock isn't cheap on a current NAV basis. Non-bull fair value (base + bear weighted) is $7.82 — the stock trades 21% above that. This is a probability edge, not a discount: market implies 11% bull probability, we estimate 25%.

Forward alpha:

Raw EV return:           +22.2%
Less risk-free:          -5.0%
Less hedge cost:         -1.5%
Net excess:              15.7%
Edge-adjusted (50%):      7.9%
Conviction-adj (60%):     4.7% net annualized alpha

Sizing framework:

• Common (hedged): 2-3% of GMV, short $1.49 SPY per $1 SKYH to isolate idio
• Warrant sidecar: 1% of AUM max, treat as defined-risk call option
• The warrant has EV/Price of 3.77x but 75% chance of zero — quarter-Kelly at most

Catalyst timing: The dense catalyst zone is late April to May 12. Miami Phase 2 opens, Q2 earnings land, 2026 guidance expected. This 3-week window either shifts the probability distribution from doorway to clear signal, or it disappoints and the stock retests $7-8.

Catalyst-dependent sizing: A smaller initial position with room to expand if Q2 EBITDA confirms and guidance provides modeling clarity. Post-catalyst, if the bull thesis strengthens (bear probability drops from 30% to 15%), the alpha profile expands to ≈20% and supports a larger allocation of 5-7% GMV.

The Honest Assessment

This is a doorway state, tilted 60% bull / 40% bear-or-delay. Both interpretations fit the current evidence. The pattern hasn't collapsed because: no 2026 guidance has been issued, first-vintage IRRs haven't been published, the leasing team scale-up is incomplete, and we can't tell how much of the 22% re-leasing is structural vs COVID catch-up.

The evidence stack is strong for a micro-cap — 31 active items, Geo Mean LR 1.66, cross-ticker corroboration from four independent OEMs. But the vehicle is noisy (38.8% idio, beta 1.49, SPAC stigma, 12% short interest), the re-leasing headline may overstate the sustainable rate, and the sub-bond structure introduces its own risks (2029 interest cliff, 2031 refinancing). The thesis is idiosyncratic. The vehicle is not.

The CEO is unusually candid — volunteers weaknesses before analysts ask, disclosed a one-time $5.9M upfront rent that drove December's positive cash flow headline, admitted the leasing team is too thin, tempered the 22% re-leasing expectation himself. That self-awareness is a credibility signal. He's building a system, not pitching a deal.

If the April/May catalyst sequence fires — Miami on time, EBITDA positive, guidance provided — the probability distribution shifts materially. If it doesn't, the warrant dies and the common retests lower.

Evidence