| Unit Name: | 878 Naval Air Squadron |
| Dates: | 1 March 1943 - 25 January 1944 |
| Type: | Single-seat fighter squadron |
| Role: | Fleet fighter squadron |
| Size: | Twelve aircraft |
| Command Structure: | Fleet Air Arm |
| Garrison: | See Naval air stations section for full list. |
| Garrison Label: | Home station |
| Battles: | World War II |
| Battle Honours: |
|
| Identification Symbol: | Black, the face of a wildcat white fimbriated red (1943) |
| Identification Symbol Label: | Squadron badge |
| Identification Symbol 2: | single letters |
| Identification Symbol 2 Label: | Identification Markings |
| Aircraft Fighter: | Grumman Martlet |
878 Naval Air Squadron (878 NAS) was a Fleet Air Arm (FAA) naval air squadron of the United Kingdom’s Royal Navy (RN).[1] Established in March 1943 as a fleet fighter squadron, it conducted its initial training at HMS Sparrowhawk, RNAS Hatston on Mainland, Orkney, prior to boarding HMS Illustrious in June. The squadron operated from the aircraft carrier off the coast of Iceland before delivering air support during the Salerno campaign in Italy. It ultimately disbanded at HMS Gannet, RNAS Eglinton, Northern Ireland in January 1944, with its aircraft being transferred to 816 and 1832 Naval Air Squadrons.
878 Naval Air Squadron formed at RNAS Lee-on-Solent (HMS Daedalus), Hampshire, on 1 March 1943, Lieutenant Commander(A) M.F. Fell, RN, commanding. Its role was as a Fleet Fighter squadron and it was equipped with twelve Grumman Martlet Mk IV, an American carrier-based fighter aircraft.
Following a period of training at RNAS Hatston (HMS Sparrowhawk), in Orkney, in Scotland, the squadron boarded the lead ship of her class, on 8 June and commenced operations in the Icelandic region the subsequent month. In August 1943, the aircraft carrier proceeded to the Mediterranean, where 878 Naval Air Squadron engaged in combat over the Salerno beachhead.
In October 1943, while stationed at RAF Port Ellen, on the island of Islay in Argyll and Bute, the squadron transitioned to ten Grumman Martlet Mk V fighter aircraft, which were subsequently distributed between 816 and 1832 Naval Air Squadrons upon the disbandment of 878 Naval Air Squadron, at RNAS Eglinton (HMS Gannet), in County Londonderry, Northern Ireland, on 25 January 1944.
The squadron has operated different variants of only one aircraft type:
The battle honours awarded to 878 Naval Air Squadron are:
878 Naval Air Squadron operated from a number of naval air stations of the Royal Navy, and a Royal Air Force station in the UK and also a Royal Navy fleet carrier:
List of commanding officers of 878 Naval Air Squadron: