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ASN Wikibase Occurrence # 153594
Last updated: 30 November 2021
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Type:Silhouette image of generic UH12 model; specific model in this crash may look slightly different
Hiller UH-12A (HT.1)
Owner/operator:705 Sqn FAA RN
Registration: XB475
MSN: 511
Fatalities:Fatalities: 1 / Occupants: 1
Other fatalities:0
Aircraft damage: Written off (damaged beyond repair)
Location:135 & 137 Southcroft Road, Gosport, Hampshire -   United Kingdom
Phase: Manoeuvring (airshow, firefighting, ag.ops.)
Departure airport:RNAS Gosport,(HMS Siskin), Gosport, Hampshire
Destination airport:
Ex-US Navy BuAer No 134725, supplied under MAP (Military Assistance Program). delivered 22 April 1953 to RN. Issued to 705 NAS, Gosport. Flew in the Fleet Review 15 Jun 1953 at Spithead.

Crashed and destroyed June 10 1954: control was lost after taking avoiding action when the lead aircraft turned suddenly due to mechanical problems during a practice display with 3 Hillers, 3 Dragonflies and a Whirlwind. It suffered rotor banging and autorotated heavily in the ground at Gosport, Hants. The pilot was killed. According to the following excerpt from the official Board of Inquiry accident report:

AIRCRAFT: Hiller HT1 XB 475 Hours flown 345.
ENGINE: Franklin 0-335-6 Hours run 345.
UNIT: 705 Squadron, R.N.A.S. Gosport.
PILOT: Lt. Ronald Arthur Moss, R.N. Killed.
DATE AND TIME: 10th June, 1954, 1123 hrs.

Lt. Moss took off from Gosport Aerodrome at 11:19 hrs. in company with Lt. M.H. Simpson, pilot in Hiller XB 480 and Lt. E.S. Taylor, pilot in Hiller XB 478. The Hillers were to take part in a practice flypast, echelon starboard with Lt. Simpson to starboard, Lt. Moss in the middle and Lt. Taylor to port.

At an altitude of about 300 ft., Lt. Taylor's aircraft broke away sharply upwards and to starboard. In order to avoid Lt. Taylor, Lt. Simpson broke away to starboard. The movements of Lt. Moss' aircraft was not noticed by either of the other pilots in the formation.

From the evidence of witnesses, Hiller XB475 banked to starboard and dived to avoid Lt. Taylor's aircraft, turned on its starboard side, lost height and finally crashed on its starboard side in a lane against the back gardens of some bungalows.

The uncontrolled movements of Lt. Taylor's aircraft was found to be due to slipping of the Sprag Clutch, a not uncommon occurrence with aircraft with unmodified clutches.

The local newspaper reported the accident as follows: ("Portsmouth Evening News" - Friday 11 June 1954)

"Gosport Pilot Dies in Crash.
A baby in a pram missed death by inches when a naval helicopter crashed yesterday at Gosport. The helicopter, one of a formation based on H.M.S. Siskin, crashed at the rear of 135 and 137, Southcroft Road. The pilot received injuries from which he died to-day in the Royal Naval Hospital, Haslar. He was Lieut. Ronald Arthur Moss (31), of South Wings, Gosport Road, Stubbington.

Mrs. Joan Thomas, of 135, Southcroft Road, told the Evening News that she was in her garden with her baby, Howard. As he sat in his pram, she drew his attention to formations of three large and three small helicopters which were flying over the cemetery. "I showed him the helicopters," she said, "because they were making a great deal of noise and I did not want him to be frightened. One of the small machines started to sway and came in our direction, but I did not realize it was going to crash. The next minute there was a loud bang and I was knocked off my feet by blast. I discovered afterwards that one of the blades of the machine struck the lawn only inches away from Howard's pram. The hood of the pram sheltered him from the blast and he was unharmed."

As the machine crashed it turned over and trapped the pilot. The machine carried away the whole of the fencing behind Nos 135 and 137, and snapped off a clothes post close to the ground in Mrs. Thomas's garden. Another of the formation made a forced landing in the new part of Ann's Hill Cemetery, which is adjacent to Southcroft Road, and a machine went to its assistance.

Mr. J. J. Rogers, of 270, Forton Road, said he was in the cemetery when, through the trees he saw blades revolving. At first he thought it was a water-sprinkling machine, but later realized it was a helicopter as the machine rose from the ground. Not long after this, he said, two sailors came there and told him they were looking for a helicopter which they thought had crashed. "I told them of the machine I had seen," he said. "but they told me that one had lifted out, but another one was missing."

Lieut. Moss was flying a Hiller helicopter, the smallest in use in the Royal Navy, and is the type used in the initial instruction of pilots in the handling of helicopters. Lieut. Moss, however, was an experienced pilot, and on Whit Monday took part in a demonstration at the Leeds air display. Yesterday, he was in formations that were carrying out manoeuvres to be used for the air display at the Royal Naval Air Station, Lee-on-Solent on Saturday. He was married, with three children".

In a particularly tragic twist, Lt Moss' wife had just given birth to their third child, a baby girl, on Monday 4 June 1954, leaving his wife a widow, and his new-born daughter an orphan, at five days old. As reported by the local newspaper ("Portsmouth Evening News" - Saturday 12 June 1954)

The helicopter crash in Gosport in which Lieut. Ronald Arthur Moss, of H.M.S. Siskin, lost his life is that he and Mrs. Moss were happy in the birth on Monday of their third child - a girl. They took residence at South Winds, Gosport Road, Stubbington, Lee-on-Solent, about a year ago but have been away for a long period. It is only in recent months that they returned. Their other children are a boy aged about five and a girl about seven."


1. Newspaper Report of accident: Portsmouth Evening News - Friday 11 June 1954
2. "Pilots wife gives birth to daughter 5 days before crash": Portsmouth Evening News - Saturday 12 June 1954
3. Report on funeral of pilot: Portsmouth Evening News - Wednesday 16 June 1954
4. Excerpt from official Accident Investigation Report at the National Archives (PRO Kew) file ADM 1/25339:

Revision history:

27-Feb-2013 19:52 Dr. John Smith Added
07-May-2013 14:02 Nepa Updated [Operator]
21-Feb-2020 01:20 Dr. John Smith Updated [Time, Location, Departure airport, Source, Narrative]
21-Feb-2020 01:23 Dr. John Smith Updated [Source]
24-Apr-2020 00:23 Dr. John Smith Updated [Source]
18-Aug-2020 20:11 Dr. John Smith Updated [Aircraft type]

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