323 Squadron was formed at Penrith High School in 1952 with strength of 30, at that point in time it was the only Cadet Unit in Sydney’s greater west. In 1971 the unit moved to an ex Royal Australian Air Force property at 121 Dunheved Circuit in St Marys where it remained until early 2001. At this point in time the unit moved to a temporary facility at Defence Establishment Orchard Hills. Finally in late 2001 the unit gratefully moved to its current location at RAAF Base Glenbrook.

In 2016, 323SQN was officially granted Freedom of the City of Blue Mountains by Mayor Cr. Mark Greenhill OAM, citing various community service work and the commendation for our efforts during the 2013 Winmalee bush fires.

Since it left Penrith High School, 323SQN has been located in close proximity to locations with historic relevance to the Royal Australian Air Force.

The Dunheved area north of St Marys today is a thriving industrial and commercial estate with ever expanding suburbs with over a century of growth and a ever changing appearance. But it once was timbered before being cut down and made into grazing land for sheep and other animals.

In 1941 the area was taken by the government to build a large Munitions factory. With close access to railway, the Great Western Highway and water, it was seen as a highly desirable location and being inland gave it some security from attack. A large and sprawling munitions factory was built as a part of a statewide network of factories spanning as far as Tamworth, Wagga Wagga and Broken Hill.

As the war continued in the Pacific, Europe and Africa, the factory expanded steadily with a internal train line and a station at Dunheved and north at Ropes Crossing. In 1943 additional infrastructure was built to produce phosphorus bombs for the RAAF and a mostly female work force worked 6 day weeks.

As the war wound down, so did operations at Dunheved. With a migrant hostel being established and factory space leased to private owners. The former buildings of the factory still stand to this day along with the Dunheved Train Station. In the 1950’s with the outbreak of war in Korea and the beginning of the Cold War, the former Munitions works in Dunheved could not be restarted due to the influx of private enterprise and a new premises was established with a large testing area at Ropes Crossing stretching west to the Northern Road.

Video of the St Marys Australian Defence Industries Site

In 1971 23 Flight NSW AIRTC moved from Penrith High School to a former RAAF building which was a former casualty station attached to the munitions factory and referred to as “the morgue”.

WSU – Historical Assessment – 121 Dunheved Circuit St Marys

In 1995 the St Marys ADI site began to close its operation and demolish various buildings with many ruins remaining as suburban development now encroaches on all its flanks.

NSW of Environment and Heritage – Wianamatta Conservation Plan

Lost Sydney – St Marys Munitions Factory

GLENBROOK – Glenbrook Tunnel

Snaking below the Great Western Highway is the original Glenbrook Tunnel built in 1891 , just as you pass the Lapstone off ramp as you head west, the tunnel opening exists in a small gully. The tunnel was originally built to compliment the Lapstone Zig Zag which existed east of the unit’s position. The Lucasville train platform is still standing and is part of a walk which features a old quarry and the picturesque Knapsack Viaduct.

Following the construction of the tunnel, difficulties were encountered with the loss of Thomas Lawless during a blasting operation and due to water seepage and the incline of the hill, westbound trains encountered loss of traction and became stuck in the tunnel. Another tunnel was built south of the original tunnel and in 1913 it ceased use and was converted into a mushroom farm with the caveat that the tunnel would be used by Defence in the event of war.

In 1939 the mushroom farm made way for Defence during the outbreak of World War 2. In 1942 following word that the Japanese used Chemical Weapons, a highly secretive weapons store was established at the tunnel. Mustard gas was shipped to Australia and stored in the Glenbrook Tunnel with temporary buildings established with operations at the Western end of the tunnel and a maintenance area established in the cutting at the Eastern end. This formed part a network of classified locations across Australia that would store chemical munitions to be the final defence against a Japanese invasion of Australia.

In 1946 following the end of World War 2, the weapons were disposed of in various ways. But the secretive work carried out at the Tunnel was classified long after and through the Cold War period. The tunnel was a significant part of RAAF and Blue Mountains history and a memorial plaque commemorating the work by the RAAF Armourers has been laid at the Glenbrook Bowling Club and War Memorial which 323SQN provides a catafalque party at for ANZAC and Remembrance Day commemorations.

Secrets of the Underworld – Glenbrook Tunnel

NSW Office of Environment and Heritage – Glenbrook Tunnel & Mustard Gas

GLENBROOK – Lapstone Hotel & Headquarters Air Command

The area surrounding the current RAAF Base has a long history of being owned by a politician and shipping magnate. In 1930 Lapstone Hill Hotel was established and offered great views of the Sydney basin area overlooking Penrith and St Marys.

With the outbreak and of war and on the back of a depression the Hotel was offered to the government in 1950 and the RAAFs Eastern Area Command originally in the Sydney suburb Edgecliffe moved to the location, given its generous radio coverage of the Sydney basin.

The art deco designed Lapstone Hill Hotel was originally used for Air Command until 1980 when various works added Airmens, Sergeants quarters and the Headquarters Air Command building which features close to the front gate. The hotel was converted into the Officers mess with further works in 1994 keeping the art deco style.

Following the decision to relocate 323SQN, a former workshop of RAAF Base Glenbrook found opposite the front gate was refurbished to accommodate the cadets. With air conditioning, classrooms and stores being created to service the needs of about 75 cadets and staff. The first event at the location was the 2001 323SQN Final Parade.

Headquarters Air Command remains a vital part of the Royal Australian Air Force and they support 323SQN with various activities with our Final Parade being held at the base since 2002, allowed for POLAIR to land at the helicopter landing pad for a Careers Day event and in 2016 our Freedom of the City challenge was conducted outside the front of the officers mess.

HQAC call upon 323SQN cadets to assist with various other events such as a Rifle Drill display for the 95th Anniversary garden party, biennial fireworks displays at Lapstone Primary School, Base Opens Days in years passed and a Defence Family Funday.