Estate and Gift Tax Valuation of Closely Held Hangar Entities

ABSTRACT

Airport hangars held through family limited liability companies and limited partnerships constitute a distinct and analytically underserved category of closely held business interest. Unlike conventional real estate holding entities, hangar LLCs carry a primary asset, an aviation ground leasehold, that is simultaneously finite in duration, non-transferable without airport authority consent, and subject to reversion-without-compensation clauses that eliminate improvement residuals at lease expiration. These structural features render standard Discount for Lack of Marketability (DLOM) and Discount for Lack of Control (DLOC) benchmarks derived from restricted-stock and closed-end-fund studies systematically inapplicable without aviation-specific adjustment. This paper develops the first integrated analytical framework for estate and gift tax valuation of hangar ownership entities. Drawing on ground lease theory, business valuation doctrine under USPAP Standard 9, and Tax Court precedent on entity-level discounts, the paper argues that lease-term-sensitive DLOM and DLOC ranges are required by both economic logic and professional standards, and that practitioners who apply generic benchmarks to wasting-asset leaseholds expose their clients and themselves to heightened IRS examination risk. A proposed discount matrix, keyed to remaining lease term, transfer restriction severity, and airport authority consent rights, provides a defensible starting framework for estate planners, business valuators, and aviation attorneys.

Keywords: airport hangar valuation, estate and gift tax, DLOM, DLOC, ground lease, reversion-without-compensation, USPAP Standard 9, family LLC, family limited partnership, business enterprise valuation, aviation leasehold

I. Introduction: The Estate Planning Problem at the End of the Runway

Consider a straightforward estate planning scenario. A 74-year-old aviation entrepreneur owns 100 percent of a Texas limited liability company. The LLC's sole meaningful asset is a ground lease from a municipal airport authority covering 1.8 acres of airside land, on which the LLC has constructed, at a cost of $3.2 million, a 25,000-square-foot corporate hangar complex that generates approximately $310,000 of annual net operating income from creditworthy sub-tenants. The ground lease has 18 years remaining with one five-year renewal option that requires airport authority consent. The operating agreement contains a right of first refusal in favor of the airport authority, prohibits assignment without the authority's written approval, and grants the authority a repurchase option at appraised improvement value upon any ownership transfer. The hangar improvements revert to the authority without compensation at lease expiration.

How should this LLC interest be valued for federal estate tax purposes?

The answer requires integrating three bodies of doctrine that rarely appear in the same analysis: (1) aviation ground lease economics, (2) business valuation methodology under USPAP Standard 9, and (3) the Tax Court's evolving jurisprudence on entity-level discounts for closely held interests. Each body of doctrine is reasonably well-developed in isolation. The interaction among them, in the specific context of aviation leaseholds, has received essentially no academic treatment.

This gap matters. The Federal Aviation Administration's National Plan of Integrated Airport Systems identifies approximately 5,400 public-use airports across the United States. Corporate hangars and FBO facilities at those airports represent tens of billions of dollars in infrastructure, a disproportionate share of which is held through family LLCs or limited partnerships created by high-net-worth aviation entrepreneurs, operating corporations, or multi-generational family businesses. As these interests pass through estates, estate planning attorneys, business valuators, and appraisers are applying generic DLOM and DLOC benchmarks calibrated to publicly traded markets to assets whose fundamental economics differ in ways that those benchmarks do not capture.

This paper addresses that gap. Section II explains why family LLCs and limited partnerships dominate hangar ownership structures for corporate and FBO facilities. Section III analyzes how reversion-without-compensation clauses affect the underlying asset value of the entity. Section IV examines the applicability and limits of standard DLOM and DLOC benchmarks when the underlying collateral is a finite, wasting aviation leasehold. Section V surveys how IRS challenges to entity-level discounts in Tax Court uniquely apply to hangar LLCs given the non-standard nature of their primary asset. Section VI proposes an analytical framework for defensible discount ranges tied to remaining lease term, transfer restriction language, and airport authority consent rights. Section VII addresses the application of USPAP Standard 9 to business enterprise valuations whose primary asset is an aviation leasehold, with specific attention to competency requirements and scope of work decisions.

II. Why Family LLCs and Limited Partnerships Dominate Corporate and FBO Hangar Ownership

A. The Operational Logic of Entity Ownership

Individual direct ownership of corporate hangars and FBO facilities is comparatively rare. The reasons are structural, not incidental. Airport ground leases routinely require the lessee to maintain substantial insurance coverage, assume environmental remediation liability, fund capital improvements on a fixed schedule, and comply with the airport's minimum standards for operations. These obligations carry meaningful personal liability exposure that individual ownership is poorly suited to contain. Entity ownership (whether an LLC, limited partnership, or corporation) interposes a liability shield between the owner's personal assets and the operational risks of aviation real estate.

For FBO facilities, the liability case for entity ownership is even stronger. FBOs sell aviation fuel, a product that creates PFAS contamination exposure, spill liability, and fire risk. They provide ground handling and aircraft towing, activities that create aviation liability claims. They frequently hold through-the-fence agreements that impose public access obligations. Concentrating these liabilities in a dedicated entity insulates the owner's other assets and simplifies insurance structuring.

Beyond liability, entity ownership facilitates co-investment. The economics of corporate hangar development (construction costs of $250 to $400 per square foot for quality facilities, plus ground lease premiums and infrastructure investment) frequently exceed what individual owners can justify based solely on their own aircraft storage needs. Partnerships allow two to eight aircraft owners to share costs, divide tax benefits, and collectively justify facility quality that none could achieve individually. Entities also enable leverage: institutional lenders prefer to take security interests in LLC membership interests rather than in individual ground lease assignments, simplifying both underwriting and foreclosure.

B. Estate Planning Motivations

Estate planning considerations reinforce the operational logic of entity ownership. Family LLCs and limited partnerships allow senior family members to transfer economic interests in aviation assets to younger generations while retaining management control (through a managing member or general partner position) and while applying entity-level discounts that reduce transfer tax values below the entity's underlying asset value. The Internal Revenue Service has recognized this structure's prevalence in the estate planning context and has devoted considerable enforcement attention to it, a dynamic discussed in Section V.

For aviation assets specifically, the multi-generational holding rationale is compelling. Ground leases at preferred airports are scarce and, once surrendered, may be irreplaceable. A family that has operated from a specific airport for decades may attach substantial value, beyond pure income economics, to maintaining continuous leasehold possession through estate transfers. Entity ownership enables that continuity without triggering the airport authority's consent rights that would typically accompany an individual ownership transfer.

C. Common Structural Variations

Several structural variations appear frequently in practice. The most common is a single-purpose LLC whose sole asset is a ground lease and the improvements constructed thereunder, with the LLC held entirely by one family or operating corporation. A variant involves a tiered structure: an operating LLC that holds the ground lease and manages the hangar sub-leasing, capped by a family limited partnership that holds the LLC membership interest and through which the economic ownership is distributed to family members. A third common structure uses a corporate FBO entity that owns the ground lease alongside the service business assets (fuel inventory, equipment, customer contracts), requiring a careful allocation between real property value and business enterprise value for estate tax purposes.

Each structural variation creates distinct valuation challenges. The single-purpose LLC is analytically cleanest: the entity value approximates the leasehold value, adjusted for entity-level discounts. The tiered structure introduces two layers of entity discount analysis, one at the LLC level and one at the limited partnership level, that the appraiser must carefully avoid double-counting. The integrated FBO entity requires a preliminary business enterprise valuation with real property segregation before entity-level discounts can be applied.

III. Reversion Without Compensation: Effect on Underlying Asset Value

A. The Reversion Clause Mechanism

The single most important economic feature distinguishing airport ground leases from conventional commercial ground leases is the reversion-without-compensation clause. In standard commercial ground leases (governing fast-food pad sites, bank branches, or industrial net-lease facilities), the tenant either retains the right to remove improvements at lease expiration or receives compensation from the landowner for structures that cannot be practically removed. Airport ground leases routinely provide neither. A typical clause reads substantially as follows: 'All improvements constructed by Lessee on the Leased Premises shall, upon expiration or earlier termination of this Agreement, become the property of the Airport Authority without compensation to the Lessee.' The consequence is straightforward but analytically significant: the improvement residual, the terminal value contribution from the hangar building that would ordinarily anchor a portion of the property's value, is zero.

This is not merely a theoretical concern. In a DCF valuation of a hangar leasehold with, say, 15 years remaining, the terminal value in year 15 would ordinarily represent a meaningful fraction of total indicated value. Under a reversion-without-compensation clause, that terminal value is eliminated entirely. The authority to require reversion derives from FAA Grant Assurance 38, which permits airport sponsors to impose reversion clauses as conditions of hangar construction approvals on airport property. The clause is therefore not a negotiating artifact that sophisticated lessees can routinely negotiate away; it is a structural feature of the airport ground lease that FAA policy affirmatively enables.

B. Quantifying the Value Impact: Three Amplifying Features

Research on ground lease capitalization rates documents that aviation leaseholds trade at larger lease-term discounts than comparable commercial ground leases (Carter, forthcoming). Three structural features amplify the discount specifically in the aviation context.

First, as described above, the reversion clause eliminates improvement residuals that would mitigate terminal-value risk in other ground lease types. A retail ground lease expiring in 15 years on a premium urban parcel retains some residual value because the tenant can sell its leasehold interest (or the franchisor's real estate subsidiary can exercise a purchase option) at a price reflecting the location premium. No comparable private market exists for aviation leaseholds because the building sits on controlled airport property with federal grant assurance obligations that prohibit non-aviation use.

Second, the hangar building is a single-purpose asset. The clear-span structure, oversized bifold doors, reinforced floor slabs calibrated for aircraft wheel loads, and airside access requirements make the hangar functionally efficient for aviation use but essentially non-convertible to alternative uses. A retail or industrial building approaching the end of a ground lease retains some option value associated with adaptive reuse. A hangar approaching the end of an airport ground lease has no such option. The building cannot be repurposed; it cannot even be moved economically. Its entire value derives from continued aviation use at that specific airport location.

Third, the airport authority's monopsony position at lease renewal eliminates the competitive tension that ordinarily disciplines landlord behavior in commercial real estate. At renewal, the authority is the sole potential lessor for the tenant's existing location. The tenant cannot credibly threaten to relocate without abandoning the reversion-bound building and incurring full replacement construction costs at a new location, a cost that, for a $3 million hangar, is prohibitive relative to any rent savings. This asymmetric bargaining position compresses the economic value of renewal options and amplifies the discount as the remaining term shortens, because the window during which the authority can exploit this leverage narrows relative to the time remaining.

C. Implications for Entity-Level Valuation

For the estate valuator, the reversion clause's most important implication is that the net asset value (NAV) calculation underlying any entity-level DLOM and DLOC analysis must reflect a leasehold value, not a fee simple or even standard leasehold value, that incorporates the zero-terminal-value constraint. A valuator who derives entity NAV from a cap rate analysis calibrated to conventional industrial real estate, without adjusting for the reversion clause and its amplifying features, will systematically overstate the NAV on which discounts are then applied. The compound error, inflated NAV multiplied by under-discounted entity value, can produce estate tax valuations that significantly overstate the interest's fair market value.

Proper NAV calculation for a hangar LLC should proceed through three steps: first, value the leasehold interest using a DCF approach with terminal value set to zero (or to any contractually specified compensation, which is often zero) and a discount rate that reflects the lease-term-sensitive risk premium documented in the aviation capitalization rate literature; second, subtract from this leasehold value any outstanding obligations (ground rent arrears, deferred maintenance reserves, environmental remediation liabilities) that would be assumed by a hypothetical purchaser of the leasehold; and third, apply entity-level discounts to the resulting NAV reflecting the marketability and control impairments created by the LLC structure itself. Each step involves distinctly aviation-specific analytical considerations that the following sections address.

IV. DLOM and DLOC in Aviation Leasehold Entities: Standard Benchmarks and Their Limits

A. The Standard Benchmarks

Business valuators approach DLOM through several established methodological frameworks. The restricted stock studies (including the original SEC Institutional Investor Study, the Silber study, and numerous subsequent empirical analyses) document discounts ranging from approximately 13 to 35 percent for restricted shares of publicly traded companies compared to their freely traded counterparts. Pre-IPO studies (comparing private company transaction prices to subsequent IPO prices) document discounts in the range of 35 to 50 percent. Quantitative models such as the Longstaff bound, the Finnerty average-strike put, and various option-pricing frameworks attempt to derive theoretical DLOM estimates from the cost of synthetically manufacturing liquidity for an illiquid interest.

DLOC studies, drawing primarily on the closed-end fund discount literature and minority interest transaction databases such as those compiled by Mergerstat and FMV Opinions, document control premiums in publicly acquired transactions of approximately 20 to 40 percent, from which corresponding minority interest discounts of approximately 17 to 29 percent are inferred. These benchmarks are commonly applied to family LLC interests on the grounds that a minority membership interest, lacking the ability to force distributions, liquidate the entity, or compel a sale of the underlying asset, is economically analogous to a minority interest in a closely held operating company.

B. Where Standard Benchmarks Fail for Hangar Entities

The restricted stock studies and pre-IPO studies from which DLOM benchmarks are derived share a critical assumption that is violated in the hangar LLC context: the underlying asset has positive terminal value. A restricted shareholder of a publicly traded company holds, beneath the marketability restriction, an interest in a going-concern enterprise whose equity residual is presumed to have positive and growing expected value. A pre-IPO investor holds an interest that, if the IPO proceeds, will become freely tradable at a price reflecting the company's going-concern valuation. The restricted-stock DLOM quantifies the discount attributable to the restriction on trading, not to any degradation in the underlying asset's value over time.

A hangar LLC interest, by contrast, holds beneath the entity-level restriction an asset that is declining in value by definition, because each year of the ground lease that passes is a year of income foregone without terminal value recovery. The marketability restriction in the hangar LLC context is not merely a temporal impediment to trading; it coincides with a structural wasting of the underlying collateral. This creates a compounding discount effect that no standard DLOM study has attempted to quantify.

Consider the mechanics. A hypothetical buyer of a 30-percent membership interest in a hangar LLC with 15 years remaining on the ground lease faces not only the standard illiquidity discount associated with a closely held interest (inability to compel redemption, thin buyer market, lack of public price discovery), but also a time-sensitive decay in the underlying asset. If the buyer cannot sell the interest for five years (a reasonable liquidity horizon for a private equity real estate fund), the underlying leasehold will have only 10 years remaining at the earliest exit opportunity, at which point the Carter (forthcoming) lease-term discount curve indicates a capitalization rate premium of 150 to 225 basis points above the long-run baseline. The buyer must therefore discount both for present illiquidity and for anticipated future value erosion caused by lease-term shortening. No standard DLOM model captures this compounding effect.

The DLOC analysis is similarly distorted. Standard minority interest discount theory assumes that the controlling interest's value, the benchmark from which the minority discount is calculated, is itself stable or growing. In a hangar LLC context, even the controlling interest is subject to the wasting-asset constraint: the managing member cannot compel the airport authority to renew the lease, cannot extract the improvement value at expiration, and faces the same monopsony negotiating dynamics as any other leaseholder. The control premium associated with managing member status in a hangar LLC is correspondingly diminished relative to the control premium associated with a controlling equity interest in a going-concern enterprise. Applying a full minority interest discount derived from acquisition premium studies to an interest in a wasting-asset entity therefore double-counts the control-related value reduction.

C. Toward Aviation-Specific Adjustments

Reconciling standard benchmarks with the hangar leasehold context requires three adjustments that a competent aviation leasehold valuator should explicitly address in the written report.

First, the DLOM should be adjusted upward from standard restricted-stock benchmarks to reflect the wasting-asset increment, the additional discount attributable to the time-sensitive decay in underlying asset value that will occur during the expected holding period for the subject interest. This increment is a function of the remaining lease term, the anticipated holding period, and the slope of the lease-term discount curve over that interval.

Second, the DLOC should be adjusted to reflect the reality that the managing member's control is partially illusory with respect to the entity's primary asset. The managing member cannot force a favorable lease renewal, cannot prevent the reversion, and cannot extract improvement value at expiration. To the extent that standard control premium studies capture the value of actions that the managing member in a hangar LLC cannot take (asset liquidation, major capital restructuring, lease restructuring), those premium components should be excluded from the baseline against which the minority interest discount is calculated.

Third, the combined discount should be adjusted to reflect any transfer restrictions specific to airport leasehold assignments, particularly airport authority consent rights, that are not captured in generic operating agreement restriction analysis. The consent right is not merely a drafting formality; it is an economically meaningful veto power held by a party with strong economic incentives to restrict transfers that might result in below-market renewal terms or non-aviation use of the facility. The consent right imposes an illiquidity cost beyond the standard minority interest discount.

V. IRS Challenges in Tax Court: How Standard Doctrine Applies and Misapplies to Hangar LLCs

A. The IRS Enforcement Landscape for Closely Held Entities

The Internal Revenue Service has pursued entity-level discount positions in estate tax contexts with sustained attention since the early 1990s. The Service's primary challenges have proceeded on two tracks: substance-over-form and step-transaction arguments challenging the entity's respect as a separate legal person, and expert testimony challenges disputing the magnitude of DLOM and DLOC applied by the taxpayer's appraiser. The Tax Court's decisions in Estate of Strangi, Estate of Bongard, Estate of Holman, and numerous related cases have established that family limited partnerships and LLCs will be respected as bona fide entities for estate tax purposes if they exhibit genuine non-tax business purposes, are properly formed and maintained, and are not funded with assets immediately needed for the decedent's personal maintenance. The Court has consistently upheld meaningful entity-level discounts for well-maintained entities while rejecting discounts claimed for entities that lacked economic substance.

For hangar entities, this existing framework presents both opportunities and distinctive risks. On the opportunity side, hangar LLCs typically possess powerful non-tax business rationale: liability containment for aviation operations, co-investment facilitation, financing structure optimization, and generational continuity of ground lease rights. A family hangar LLC that actively sub-leases hangar bays, manages tenant relationships, complies with airport minimum standards, and maintains proper books is unlikely to be disregarded as a mere tax vehicle. The business reality is too evident.

B. Distinctive IRS Arguments in the Hangar Context

However, the IRS may advance several arguments in the hangar context that have no direct precedent in the standard family limited partnership case law. The first concerns the circularity of valuing a wasting-asset entity using DLOM benchmarks derived from going-concern study populations. A Service expert could credibly argue that applying a 30-percent DLOM derived from restricted-stock studies to an interest in an LLC whose primary asset is a 14-year wasting leasehold produces a discount that exceeds what market participants would actually pay, because the expected holding period discount already embedded in the leasehold NAV partially captures the same illiquidity effects that the restricted-stock DLOM purports to measure.

The second distinctive IRS argument concerns the airport authority's consent right as a value floor. If the LLC operating agreement or the underlying ground lease contains a provision giving the airport authority the right of first refusal at appraised value upon any transfer of the membership interest or the underlying leasehold, the authority's consent right effectively establishes a floor on transfer value. The Service could argue that a floor at appraised value significantly reduces the DLOM available to the taxpayer, because the hypothetical buyer knows that a willing seller, the airport authority, exists at that price. This argument has no analog in the standard family limited partnership context, where no government entity holds a contractual right of first refusal on the underlying assets.

The third distinctive argument involves the ground lease's reversion clause and its effect on the entity's going-concern status. In contested estate valuations, the IRS has sometimes argued that the appropriate valuation premise for a closely held entity holding wasting assets is liquidation value rather than going-concern value. For a hangar LLC with fewer than ten years remaining on an unrenewable ground lease, the liquidation valuation premise may not be unreasonable: a hypothetical buyer might rationally assume that the entity will wind down as the lease expires rather than attempt to relocate operations. If the liquidation premise is adopted, the DLOM and DLOC arguments substantially change, because the discount for lack of marketability in a liquidating entity is a function of the liquidation timeline and costs, not of the going-concern operating restrictions that standard restricted-stock studies measure.

C. Managing IRS Examination Risk

Estate practitioners and valuators representing hangar LLC interests should anticipate these distinctive arguments and address them affirmatively in the written valuation report. A report that simply applies standard DLOM and DLOC benchmarks without acknowledging the wasting-asset context (or, worse, one that does not identify the ground lease reversion clause as a primary value driver) is likely to be successfully challenged on examination. Defensible practice requires explicit quantification of the wasting-asset DLOM increment, explicit analysis of the airport authority consent right's effect on marketability, and explicit consideration of the appropriate valuation premise given the remaining lease term and renewal option structure.

Conversely, practitioners who over-discount by applying aviation-specific DLOM increments without supporting analysis are equally exposed. The Tax Court has consistently rejected DLOM positions that are not grounded in specific, quantifiable impairments to the subject interest's marketability. An aviation-specific DLOM increment must be tied to specific features of the hangar leasehold (lease term, reversion clause, consent right severity, transfer restriction language) rather than to generalized assertions about aviation real estate's illiquidity.

VI. A Proposed Analytical Framework for Defensible Discount Ranges

A. Framework Architecture

The proposed framework proceeds in four stages. Stage 1 establishes the leasehold NAV as the valuation foundation using a DCF approach with terminal value set to zero, discounted at a rate incorporating the empirical lease-term risk premium from the aviation capitalization rate literature. Stage 2 identifies and quantifies the transfer restriction severity score using three inputs: the restrictiveness of operating agreement transfer provisions, the scope and terms of airport authority consent rights, and the presence or absence of right-of-first-refusal provisions in favor of the authority or co-members. Stage 3 calculates the wasting-asset DLOM increment as the expected present value of additional leasehold value decay that will occur during the expected holding period for the subject interest. Stage 4 combines the standard DLOM and DLOC benchmarks, adjusted for transfer restriction severity, with the wasting-asset increment to produce an integrated entity-level discount recommendation.

B. Transfer Restriction Severity Score

Transfer restrictions in hangar LLC operating agreements typically cluster around four provisions, each of which affects marketability independently: (1) a right of first refusal exercisable by existing members at fair market value or at a formula price; (2) a requirement that transfers receive approval from all or a supermajority of members; (3) a prohibition on transfers to non-family members without managing member consent; and (4) a requirement that the airport authority consent to any transfer of the LLC interest or the underlying leasehold. The first three provisions are common in family LLC operating agreements generally and are addressed by standard DLOM analysis. The fourth is aviation-specific and requires separate treatment.

The airport authority's consent right ranges from a simple notification requirement, which adds transaction friction but does not give the authority effective veto power, to a substantive approval standard under which the authority may withhold consent if the proposed transferee does not meet the authority's operational and financial standards. Many airport ground leases include consent standards that are deliberately broad, giving the authority discretion to reject any transferee who the authority determines may not operate the facility in a manner consistent with the airport's minimum standards or its long-term development plans. Under such a standard, the authority effectively holds a veto on all ownership transfers, which is economically equivalent to a right of first refusal exercisable at zero cost. A valuator assigning a severity score should document specifically which consent standard applies and assess its practical effect on the hypothetical buyer pool.

C. The Wasting-Asset DLOM Increment

The wasting-asset DLOM increment quantifies the additional discount attributable to leasehold value decay during the expected holding period for the subject interest. It is calculated as follows. Let T denote the remaining lease term at the valuation date, and let H denote the expected holding period for the interest (typically three to seven years for a private real estate holding, but potentially longer for a family estate planning context). The increment is the difference between the present value of the leasehold at T years remaining and the present value of the leasehold at T-H years remaining, expressed as a percentage of the current leasehold value. This calculation requires the empirical lease-term discount curve, specifically, the increase in capitalization rate premium that will occur as the lease moves from T years remaining to T-H years remaining. Using the discount curve published in Carter (forthcoming), this increment can be calculated for any combination of T and H within the range of empirical observations.

For illustration, consider a leasehold with 17 years remaining (placing it in the 150-basis-point premium tier) and an expected five-year holding period. At 12 years remaining (after the five-year hold), the expected capitalization rate premium is approximately 190 basis points above the long-run baseline, an increment of 40 basis points. Applied to a property generating $300,000 in NOI, this 40-basis-point increment reduces indicated value by approximately $200,000 at current rates, a decay of roughly 5 to 7 percent of current leasehold value. This decay is incremental to the standard DLOM and represents the wasting-asset component that no restricted-stock study captures.

D. Integrated Discount Matrix

Table 1 presents the proposed integrated discount matrix organizing suggested total entity-level discount ranges by remaining lease term. The matrix is intended as a starting framework, not a mechanical formula. Each engagement requires independent analysis of the specific operating agreement, ground lease terms, airport authority consent standards, and market conditions. Departures from the matrix ranges must be documented with specific supporting evidence.

Table 1: Proposed Integrated Entity-Level Discount Framework for Hangar LLCs

Note that the combined discount ranges in Table 1 assume a minority interest of 20 to 49 percent of membership interests, standard consent-required transfer restriction language, and no exceptional characteristics (such as a pending lease renewal negotiation or a documented offer from the airport authority at a specified price) that would independently anchor the value. Each of these factors modifies the applicable range and must be analyzed in the written report.

VII. USPAP Standard 9: Business Enterprise Valuation of Aviation Leasehold Entities

A. Standard 9 Requirements and Their Application to Hangar LLCs

USPAP Standard 9 governs business appraisal development and requires that the appraiser identify the business enterprise, business ownership interest, or security subject to appraisal; identify the interest to be valued; identify the effective date; identify relevant characteristics of the subject; define the value being developed; and develop a workscope sufficient to produce a credible opinion. Standard 9 applies to the valuation of a hangar LLC membership interest because the subject is a business ownership interest whose value is determined by reference to the underlying enterprise, the LLC, rather than by reference to the real estate asset directly.

The competency requirement of USPAP is particularly relevant in the hangar LLC context. An appraiser who accepts a Standard 9 engagement to value a membership interest in an LLC whose primary asset is an aviation ground leasehold must possess competency in three areas: business enterprise valuation methodology (including entity-level discount analysis), real estate leasehold valuation (including aviation-specific ground lease analysis), and aviation real estate market conditions. This is a demanding competency combination. The business valuator who lacks aviation real estate expertise will not be able to competently estimate the NAV underlying the entity-level discount analysis. The real estate appraiser who lacks business valuation expertise will not be able to competently apply entity-level DLOM and DLOC methodology. Neither professional, acting alone and outside their competency zone, can produce a Standard 9-compliant opinion of a hangar LLC membership interest without either acquiring the missing competency or engaging a qualified associate.

B. Scope of Work Decisions

The scope of work decision under Standard 9 requires the appraiser to identify what research and analysis is necessary to develop a credible opinion. For a hangar LLC membership interest, a credible scope of work should include, at minimum: review and analysis of the ground lease agreement in its entirety, including reversion clause, renewal option terms, and consent requirements; review of the LLC operating agreement with specific attention to transfer restriction provisions and managing member authority; inspection of the hangar improvements and assessment of their remaining economic life under the lease term; review of all sub-lease agreements and tenant creditworthiness; analysis of the airport's competitive position, minimum standards, and authority's stated development plans; application of the DCF approach to the leasehold interest with terminal value set per the reversion clause; and application of entity-level DLOM and DLOC analysis with explicit adjustment for the wasting-asset increment and transfer restriction severity.

A scope that omits any of these elements is likely inadequate for a complex hangar LLC, though smaller or simpler entities may justify a more limited scope with appropriate limiting conditions. Any material limitation must be disclosed in the written report with an explanation of why the omission does not compromise the credibility of the opinion.

C. Reporting Requirements and IRS Qualified Appraisal Standards

For estate and gift tax purposes, the valuation report must also satisfy the IRS qualified appraisal requirements under Treasury Regulation 1.170A-17 and Revenue Procedure 66-49, as applied to estate tax appraisals under Section 2031. A qualified appraisal must be conducted by a qualified appraiser, defined as one who holds a recognized credential, has verifiable education and experience in valuing the type of property at issue, and is not related to the taxpayer. For hangar LLC interests, the requirement that the appraiser have verifiable experience in valuing 'the type of property at issue' creates a meaningful credentialing standard. A business valuator with no aviation real estate experience does not satisfy this standard for the leasehold NAV component. A real estate appraiser with no business valuation credentials does not satisfy it for the entity-level discount component.

The IRS's increasing scrutiny of aviation asset valuations (noted in the Service's published examination guidance for Form 706 estate returns involving closely held businesses) makes the credentialing question more than academic. An estate that relies on a valuation performed by an appraiser lacking genuine aviation real estate expertise for the NAV component, or business valuation expertise for the DLOM/DLOC component, faces heightened examination risk. The penalty provisions of Section 6695A, which impose appraiser-level penalties for substantial appraisal overstatements, apply to the appraiser directly and create meaningful professional liability exposure.

Best practice is for the hangar LLC valuation engagement to be structured as a collaboration between a credentialed business valuator (ASA, ABV, or CVA designation) and an aviation real estate specialist with documented expertise in ground lease valuation. The report should clearly identify each professional's contribution, credentials, and scope of responsibility. This structure satisfies USPAP Standard 9's competency requirement, addresses the IRS qualified appraiser standard for each component of the valuation, and provides the clearest possible defense in the event of examination.

VIII. Conclusion

The estate and gift tax valuation of closely held hangar ownership entities sits at a challenging intersection of real estate appraisal, business valuation, and aviation law. The dominant LLC and limited partnership structures that organize corporate and FBO hangar ownership carry, as their primary asset, aviation ground leaseholds that differ from conventional commercial real estate in economically material ways: reversion-without-compensation clauses eliminate improvement residuals, single-purpose building constraints eliminate adaptive-reuse option value, and airport authority monopsony eliminates the competitive discipline that ordinarily constrains ground landlord behavior. These features amplify lease-term discounts beyond what conventional ground lease theory predicts and render standard DLOM and DLOC benchmarks systematically misapplicable without aviation-specific adjustment.

This paper has proposed a framework addressing each dimension of this problem: an adjusted NAV methodology that explicitly incorporates the zero-terminal-value constraint; a transfer restriction severity analysis that addresses the airport authority's consent rights as an independent marketability impairment; a wasting-asset DLOM increment quantifying the additional discount attributable to leasehold value decay during the expected holding period; and an integrated discount matrix organizing these adjustments by remaining lease term. The framework is grounded in aviation ground lease economics, USPAP Standard 9 doctrine, and Tax Court precedent on entity-level discounts.

The practical stakes are significant. As the first wave of aviation entrepreneurs who built the corporate hangar market of the 1980s and 1990s approaches estate settlement, the volume of hangar LLC and FBO partnership interests passing through estates will grow. The appraisers, estate attorneys, and business valuators serving those estates face genuinely novel analytical challenges that the existing valuation literature does not address. This paper is offered as a starting framework for meeting that challenge, with the expectation that empirical research, peer scrutiny, and practitioner experience will refine and extend it in the years ahead.

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About the Author

Clay W. Carter, DBA, MBA, MS, CFA, FRM, CAIA, CIPM, is a Professor of Finance at Embry-Riddle Aeronautical University and founder of Valuation Takes Flight, LLC, an aviation real estate valuation firm. His research focuses on airport hangar valuation methodology, ground lease economics, and the application of financial theory to aviation-specific real estate problems. Correspondence: valuationtakesflight.com.

This paper is research and general information for professionals evaluating aviation real estate. It is not appraisal, legal, or tax advice, and it does not create an engagement.