Civil Aviation

Hangar One so Large it has its Own Microclimate

Hangar One stands as one of the world’s largest independent structures, spanning 8 acres at Moffett Field near Mountain View, California.

Located in the San Francisco Bay Area, it prominently marks California’s Silicon Valley. Constructed in the 1930s, it originally served as a naval airship hangar for the USS Macon. Currently, it resides as part of the NASA Ames Research Center.

Incredible Design

Dr. Karl Arnstein, a German airship and structural engineer, designed Hangar One with Wilbur Watson Associates Architects and Engineers.

Hangar One at Lakehurst is based on the typical designs of World War I. It resembles many of the rigid airship hangars built in Great Britain which used counter-balanced doors in lieu of the steel supporting framework generally found in German hangar design.

Situated in Akron, Ohio, Arnstein was Vice President and Director of Engineering for the Goodyear Zeppelin Corporation.



The hangar showcases a network of steel girders, all sheathed with galvanized steel. Moreover, it sits on a reinforced pad that’s anchored to concrete pilings.

Covering 8 acres, its floor can host six 360-by-160-foot American football fields.

Notably, the airship hangar spans 1,133 feet in length and 308 feet in width.



The building embraces an aerodynamic architecture, with walls curving inward to create an elongated, approximately catenary form, reaching 198 feet high.

Designed to mitigate turbulence during the USS Macon’s entries and exits on windy days, the clam-shell doors weigh 200 short tons each.

Furthermore, each door operates with its own 150-horsepower motor, managed through an electrical control panel.

USS Macon

The USS Macon (ZRS-5), a rigid airship, was built and operated by the United States Navy, primarily for scouting.

USS Macon docked inside Hangar One at Moffett Field.

Additionally, it functioned as a “flying aircraft carrier,” harboring up to five single-seat Curtiss F9C Sparrowhawk biplanes or two-seat Fleet N2Y-1s for training.



Unfortunately, after less than two years in service, the Macon suffered damage in a storm and was lost off California’s Big Sur coast in February 1935.

Thankfully, most of the crew members were saved. The wreckage now resides on the U.S. National Register of Historic Places as the USS Macon Airship Remains.

Comparatively shorter than the Hindenburg by less than 20 ft (6.1 m), the Macon and its sister ship, Akron, were among the world’s largest flying objects, both in length and volume.

Despite the hydrogen-filled, Zeppelin-built Hindenburg and LZ 130 Graf Zeppelin II being longer, Macon and Akron maintain the world record for the largest helium-filled rigid airships.

The Goodyear-Zeppelin Corporation, located at the Goodyear Airdock in Springfield Township, Ohio, constructed the USS Macon at a cost of $2.45 million, which equates to $53 million in 2022, under a fixed-price contract.

German Airship Engineers

Given that it was the largest airship to be built in America, a team of skilled German airship engineers, led by Chief Designer Karl Arnstein, provided guidance and support for the design and construction of both the Akron and Macon.

Macon moored in Hangar One at NAS Moffett Field in 1933

The Macon boasted a structured duraluminum hull and three interior keels. Twelve helium-filled gas cells, crafted from gelatin-latex fabric, kept the airship aloft.



Encased within the hull, the Macon utilized eight German-made Maybach VL II 12-cylinder, 560 hp gasoline engines, which powered the external propellers.

These propellers, capable of rotating downward or backward, utilized an early form of thrust vectoring to control the airship during takeoffs and landings.

Moreover, a system that condensed water vapor from the engine exhaust gases into buoyancy compensation ballast, aiding in stabilizing the airship’s weight as fuel was consumed, was connected to the slots above each engine in the hull.

In service for less than two years, in 1935 the Macon was damaged in a storm and lost off California’s Big Sur coast

On October 15, 1933, USS Macon was inside Hangar One after a transcontinental flight from Lakehurst, New Jersey.



Remarkably, the hangar’s interior is so vast that fog sometimes accumulates near the ceiling. Standard gauge tracks permeate the hangar’s length, having once extended across the apron and into adjacent fields.

These tracks helped transport airships on a mooring mast to either the hangar interior or a flight position. During Macon’s brief tenure at Moffett, Hangar One housed it and several smaller non-rigid lighter-than-air craft simultaneously.

Ohio’s Goodyear Airdock

Hangar One shares similarities with Akron, Ohio’s Goodyear Airdock, constructed by the Goodyear Zeppelin Corporation in 1929. When the Goodyear Airdock was established, it stood as the largest world’s interior-support-free building, situated in Northeast Ohio.

Macon under construction at the Goodyear Airdock

The structure offered extensive space for building “lighter-than-air” ships, such as airships, dirigibles, and blimps.

Akron and Macon, the first two airships built and launched at the Goodyear Airdock, came to life in 1931 and 1933 respectively. Both airships measured a notable 785 feet in length.

Moreover, historic references reach back to European examples, notably the hangars d’Orly for dirigibles at the Orly Air Base near Paris.

Designed and constructed in 1921-1922 by French structural and civil engineer Eugène Freyssinet, a prominent figure in prestressed concrete, these were destroyed in World War II.

Likewise, two airplane hangars designed by Italian architect Pier Luigi Nervi in 1935, built for the Italian Air Force in Orvieto, Italy, in 1938, exemplify similar concrete construction. These, too, did not survive through World War II.

National Register of Historic Places.

On February 24, 1994, the Shenandoah Plaza National Historic District, including Hangar One, joined the National Register of Historic Places.

Subsequently, on May 20, 2008, the National Trust for Historic Preservation listed Hangar One among the 11 most endangered historic U.S. places.

Exterior panels removed, September 2012

However, 2003 brought challenges as it was discovered the structure was leaking toxic chemicals, including PCBs, into neighboring San Francisco Bay wetlands, originating from its lead paint and other materials.

Consequently, several proposals emerged, including demolishing the hangar, cleaning and refurbishing it, or a private company’s offer to coat its exterior with solar panels to offset cleaning costs, though none materialized due to various obstacles, primarily financial.

Fast forward to December 2010, the Navy commenced remediation of the PCBs, lead, and asbestos while NASA pondered the hangar’s future uses.

Amidst strong local community backing for its historical preservation, workers began removing its exterior panels in April 2011, completing the massive task in mid-2012.

Later, in October 2011, Google executives offered $33 million for Hangar One’s revamp in exchange for using some of its space for their private jets.

Then, in 2014, NASA and the General Services Administration chose Planetary Ventures, a Google subsidiary, to oversee Hangar One and Moffett Airfield, with Google agreeing to a 60-year, $1.16 billion lease.

Google disclosed its intentions to test toxic chemical removal techniques from the hangar in May 2016 and, in May 2017, announced the hangar’s restoration completion target for 2025.

Gallery

Macon over Moffett Field

Crew of U.S.S. Macon inside Hangar One with Macon dirigible on June 6, 1934. Photo Credit: U.S. Navy

Squadrons VF-6, VB-2 & VT-2 in Hangar One

Hangar One with opened orange peel doors, 1963

U.S.S. Macon moored at south circle, viewed from camera inside of Hangar One.

The hangar in 2009

HangarOne originally included a system of trolley tracks serving as docking rails for airship handling. These rails ran through the hangar and 1,500 feet from each end onto the landing areas.