Abandoned & Little-Known Airfields:

Northern Idaho

© 2002, © 2014 by Paul Freeman. Revised 12/25/14.

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Henley Aerodrome (revised 12/25/14) - Test Area North (revised 5/27/13)


Henley Aerodrome (S62), Athol, ID

47.91 North / 116.71 West (Northeast of Spokane, WA)

Henley Aerodrome, as depicted on a 9/19/76 aerial photo.

This general aviation airport was not yet depicted at all on a 1966 aerial photo nor or the 1967 USGS topo map,

nor listed in the November 1972 Flight Guide (according to Chris Kennedy).

According to Heather Hart, “Henley Aerodome was founded in 1973 as posted on [Clayton] Henley's grave stone.”

The earliest reference which has been located to the Henley Aerodrome

was its listing in the 1976 AOPA Airport Directory (according to Chris Kennedy).

The earliest depiction which has been located of the Henley Aerodrome was a 9/19/76 aerial photo.

It depicted Henley as having a single northeast/southwest runway.

The earliest aeronautical chart depiction which has been located of the Henley Aerodrome

was on the July 1977 Great Falls Sectional Chart (courtesy of Chris Kennedy).

It depicted Henley as a public-use airport with a single 2,600' paved northeast/southwest runway,

and indicated that parachute operations were conducted at the field.

An undated photo of a sign for the Henley Aerodrome Museum & Cafe,

advertising “Rides & instruction in airplanes & gliders.”

A circa 1970s aerial view of the Henley Aerodrome by Montgomery Stewart.

Montgomery recalled, “Henley took me up one afternoon in the 1970s in a Dehaviland Tiger Moth.”

A circa 1970s photo by Montgomery Stewart of several biplanes in a Henley Aerodrome hangar.

A circa 1970s photo by Montgomery Stewart of several biplanes inside a Henley Aerodrome hangar.

The November 1977 Flight Guide (courtesy of Chris Kennedy)

depicted the Henley Aerodrome as having a single 2,600' paved Runway 2/20,

with a small ramp on the southeast side.

The field was depicted as conducting parachute operations.

A 10/4/78 USGS aerial photo depicted Henley as having a single northeast/southwest asphalt runway.

In 1981 the airport was purchased by Gary Norton, founder of Spokane’s ISC Systems Corporation.

Described as “An avid pilot with a passion for vintage aircraft”, Norton sought his own airstrip & a place to store his growing collection of classic planes.

According to Wikipedia, in 1981 “Lengthening & other improvements are done to the airstrip. The hangar is turned into an air museum.”

The May 1981 Flight Guide (according to Chris Kennedy) described Hensley as having a 4,200' runway.

In 1986, after successfully outbidding Disney & others for an original 1915 Steam Engine Train,

Norton began thinking of his property as more than his own personal playground.

He imagined a transportation-inspired museum & theme park where people could see & appreciate all kinds of rare planes, trains, and automobiles.

As the park was being built, Norton changed the name to Silverwood in order to broaden the park’s appeal & pay homage to the region’s mining history.

The 1987 USGS topo map depicted the Henley Aerodrome as having a single northeast/southwest runway.

An article entitled “Aerodrome: One man's flight of fancy” appeared in the 8/11/87 Coeur D'Alene Press,

depicting owner Gary Norton in front of his Ford Trimotor.

The Silverwood Theme Park opened on 6/20/88.

Over 120,000 guests enjoyed the park’s unique Victorian-themed shops & restaurants, movie theater, and train rides that first season.

The May 1994 Flight Guide (courtesy of Chris Kennedy)

depicted the Henley Aerodrome as having a single 4,200' paved Runway 3/31.

Additional improvements had been added since 1977, including a parallel taxiway, larger ramp, and multiple buildings.

The field was said to conduct operations of gliders, aerobatics, helicopters, banner towing, parachutes,

and to have air shows.

The last photo which has been located depicting the Henley Aerodrome while in operation was a 1998 USGS aerial view.

The airfield had a single asphalt northeast/southwest runway with a parallel taxiway,

and a ramp on the southeast side with several hangars.

Note the large aircraft parked on the southeast side of the midpoint of the runway – Gary Norton's Ford Trimotor?

The Silverwood Theme Park occupied land on the south side of the airport at this point,

but had not yet expanded to cover the airport.

According to Heather Hart, “Mr. Norton purchased the airstrip from him and founded Silverwood after selling his banking software in the 1980's.”

The Henley Aerodrome was evidently closed at some point between 1998-2003.

In 2003, the Boulder Beach Water Park opened.

Unfortunately, this expansion covered the northeast end of the runway.

A 2004 aerial view looking northeast along the former runway,

showing it marked with closed-runway “X” symbols.

The far end of the runway had been covered by the Boulder Beach theme park.

But the majority of the length of the runway & taxiway remained intact,

and it appeared as if the hangars remained standing as well.

The former Henley Aerodrome is depicted as an abandoned airfield on the 2008 Sectional Chart.

The site of Henley Aerodrome is located northwest of the intersection of Route 95 & East Brunner Road.

Thanks to Al Courtney for pointing out this airfield.


Test Area North, Monteview, ID

43.86 North / 112.73 West (East of Boise, ID)

A concept for a nuclear-powered X-6, derived from the Convair B-36.

A concept for a nuclear-powered X-6, derived from the Convair YB-60 (the swept-wing development of the B-36).

A Northrop concept for a nuclear propelled bomber, refueling two other aircraft.

An undated photo of HTRE-1, also known as the Core Test Facility, the initial aircraft engine/reactor testbed, at TAN.

The HTRE-3 nuclear aircraft engine, without its test structure.

This is a rather unique case of where an extremely substantial hangar was built,

but never the accompanying runway!

The National Reactor Testing Station (known today as the Idaho National Engineering & Environmental Laboratory)

was established in 1949 in a very remote part of Idaho.

Test Area North was constructed in the early 1950s at the north end of the NRTS property,

about 27 miles northeast of the Central Facilities Area.

It was built by the USAF & the Atomic Energy Commission to support the Aircraft Nuclear Propulsion Program,

an attempt to develop a nuclear propelled bomber.

Beginning in 1955, TAN was the site of the Heat Transfer Reactor Experiments (HTRE),

which conducted ground-based testing of what was intended to be the prototype aircraft nuclear engine.

The aircraft which was intended to use this powerplant was the Convair X-6.

The X-6 was originally intended to be based on Convair's B-36 bomber,

but the design was later changed to use Convair's B-60 (the swept-wing development of the B-36) as its baseline.

The X-6 was intended to have conducted its flights from Test Area North.

A huge (350' wide) hangar to house the X-6 was constructed at Test Area North,

built with enormously thick, nuclear-shielded walls & bays.

General Electric, the program contractor,

planned to equip the engine maintenance facilities with closed-circuit television systems

and remote manipulator arms to allow technicians to work on the aircraft & its powerplant

without direct exposure to the intense radiation field that would persist even after the reactor was shut down.

Since the turbojets essentially functioned as the cooling system for the reactor,

they would have to be run at high power settings even after shutdown of the reactor

in order to maintain cooling airflow through the still-hot core.

After an initial cooldown period, ground cooling systems would be connected to the reactor

and the engines could be shut down as the reactor was extracted from the airplane & placed in its shielded storage bay.

It was estimated that the tremendous weight of a nuclear propelled X-6

would have necessitated a 15,000' runway.

Plans for such a runway were drawn up at TAN, extending to the southwest away from the hangar area,

but the runway was never constructed.

A multi-mile runway for the X-6 was also planned at Edwards AFB, CA,

running between Muroc dry lake & Rosamond dry lake, but it too was never built (see Pancho Barnes Airfield, CA).

The initial HTRE engine experiments were intended to prove out the engineering & operational concepts

for a nuclear bomber powerplant, but without the restrictions on weight & size that an airplane powerplant would demand.

These early assemblies were gigantic monstrosities weighing at least a hundred thousand pounds,

and were built on railcars which would move them to remote test locations

far from their assembly, maintenance & control facilities.

When the engineering aspects of the designs were proven,

the next step would be to reduce the size of the designs while increasing their power output,

with the goal of producing a final, operational version of the design

that would be "flightweight" & "flightsize", with a thermal output of at least 50 megawatts.

This was to be done in stages over a several year period.

Several non-flightworthy prototype nuclear aircraft engines were actually tested at the Initial Engine Test Area,

located at the north end of Test Area North.

HTRE-1, also known as the Core Test Facility, the initial aircraft engine/reactor testbed,

was mounted on a huge mobile railroad car assembly.

It was a water-moderated uranium reactor with a beryllium reflector & shielding that included large quantities of mercury.

The two jet engines just visible at lower left would be started using hot gas produced by chemical-fuel combustors.

Once the jets were running at speed, the reactor would be brought up to power & airflow would be established through the core.

Its heat would then be gradually diverted to the jet turbines as the gas combustor flow was phased out.

The jets would be run on nuclear-heated air for periods of hours at a time

to simulate the operation of a long-duration nuclear aircraft powerplant.

Post-shutdown, the reactor's railcar would be returned to a maintenance bay for disassembly & analysis.

HTRE-1 reached power levels as high as 20.2 megawatts.

General Electric began HTRE-1 test runs in 1955

and the reactor successfully powered the X39 engines the following year,

although the massive contraption was far from a practical aircraft powerplant.

However, HTRE-3 was a major step toward a flight-capable nuclear engine,

which would have been designated XNJ140E-1.

The dimensions of the core & its structural characteristics as well as the design temperatures

were those of a power plant capable of providing useful flight propulsion.

The power generated by HTRE-3 ranged up to 35 megawatts.

In the HTRE No. 3 tests, the power levels were so chosen that the fuel element temperatures, the key parameter,

would be characteristic of flight service.

The size & configuration of HTRE-3 appear to have been designed with the B-36 or B-60 in mind.

HTRE-3 was operated at the National Reactor Testing Station from 1958-60.

Although no aircraft was ever operated under nuclear propulsion,

an NB-36 testbed did fly while carrying an operating nuclear reactor.

These flights were not carried out from TAN, tough.

Having successfully operated a 35 megawatt, flightweight nuclear turbojet powerplant

that probably could have propelled a bomber-sized aircraft,

the Aircraft Nuclear Propulsion project came rather close to fulfilling the original design goals of the late 1940s.

If HTRE-3 had existed in 1952, it most likely would have flown in an aircraft,

but by 1961 the very existence of manned bombers was threatened by the cheaper, faster & relatively invulnerable ICBM.

The large nuclear airplane engine had lost its raison d'etre in the Kennedy/McNamara era,

and the ANP program was canceled in 1961.

The Initial Engine Test area is located at the north end of Test Area North.

After the Aircraft Nuclear Propulsion program ended in 1961,

the area was used for the Space Nuclear Auxiliary Power Transient Program through 1967.

A 7/11/67 USGS aerial photo showed the former X-6 hangar, and surrounding revetments for testing.

No sign of any accompanying runway was present in photos of the surrounding area.

The 1969 USGS topo map depicted the Test Area North hangar, but no other airfield-related facilities.

The Three Mile Island Unit 2 reactor core was shipped to the INEEL's Spent Fuel Program area in 1986.

The Contained Test Facility is located at the west end of Test Area North.

This facility includes the Containment & Service Building (reactor facility),

the aircraft hangar, the Reactor Control & Equipment Building, and numerous support facilities.

Preparation for deactivation of these buildings & structures began in 1996,

and included documentation of some of the historic properties, including the Nuclear Aircraft Hangar.

The former X-6 hangar is visible in the top-right of the 1998 USGS aerial photo.

No sign of any accompanying runway is present in photos of the surrounding area.

A recent aerial view looking west at the former X-6 hangar, now known as the Contained Test Facility, at TAN.

Today, Test Area North is composed of 4 areas:

the Contained Test Facility, the Technical Support Facility,

the Water Reactor Research Test Facility, and the Initial Engine Test area.

Currently, the Initial Engine Test facility is being demolished.

According to INEEL's website, "Unless it becomes necessary for the US to resume former levels of defense-related activities,

the future of Test Area North will consist of completing current programs,

deactivating all facilities, and completing environmental restoration activities."

The former X-6 hangar was still visible in a 6/24/09 aerial photo.

See also: