HANGAR 4 PARTNERS

Harold L. Yoh III serves as Chief Investment Officer and is the primary decision-maker. A former Goldman Sachs analyst with a Wharton MBA, Yoh represents the fifth generation of the family that founded Day & Zimmermann. The firm operates with a lean team structured for principal-driven allocations rather than committee-led approvals.

The wealth originates from Day & Zimmermann, an engineering and industrial services conglomerate founded in 1901 by Harold L. Yoh Sr. The company generates over $2.7 billion in annual revenue from construction, munitions manufacturing, nuclear-plant services, and staffing. It is one of the U.S. Department of Defense's key munitions contractors and a long-standing operator in critical infrastructure.

Hangar 4 sources through a combination of venture fund relationships, direct founder outreach, and the Yoh family's deep network in the defense industrial base. The family's century-long status as a DOD contractor provides access to classified program knowledge and procurement-timeline intelligence that generalist investors typically lack. The firm co-invests alongside established venture funds on select deals rather than leading priced rounds.

The firm actively co-invests alongside external general partners in venture and growth rounds, particularly those with national security or industrial technology theses. It does not act as a fund-of-funds allocator but will deploy capital into specific deals introduced by trusted venture relationships. This allows Hangar 4 to access deals beyond its own origination capabilities while maintaining direct ownership in portfolio companies.

Hangar 4 has no known exposure to consumer internet, entertainment, or pure-play software-as-a-service businesses with no government or industrial buyer path. The concentrated thesis around dual-use defense technologies, cybersecurity, and industrial automation suggests the firm deliberately avoids categories where it lacks a procurement or domain advantage.

Hangar 4 is a single family office with no external limited partners. It deploys Yoh family capital directly, though its stage-agnostic, venture-heavy deployment pattern resembles that of a principal-driven venture investor. The firm has not registered as an investment advisor and raises no outside funds.

Hangar 4 writes checks from pre-seed through growth equity, making it effectively stage-agnostic within the technology and industrial sectors it covers. Confirmed positions include venture rounds for Rebellion Defense and growth-stage exposure to Anduril Industries, indicating comfort with both early technical risk and later-stage scaling companies.