When the war started in North Africa on 10 June 1940, 80 Squadron was commanded by Squadron Leader R. C. Jonas and based at Amriya. It had 22 Gladiators (mainly Mk.Is) and one Hurricane Mk.I (L1669 – nicknamed Collie’s Battleship) on hand. Its main role was the defence of Alexandria. The pilots were divided into three Flights.
‘C’ Flight included Flight Lieutenant Ralph Evers-Swindell, Flying Officer Peter Wykeham-Barnes, Flying Officer Harold Sykes, Pilot Officer Stubbs, Pilot Officer Wanklyn Flower, Sergeant George Barker, Sergeant J. H. Clarke, Sergeant Edward Hewett and Sergeant Kenneth Russell Rew.

During the morning on 17 August, the Mediterranean Fleet was out for a raid in support of the Army. The battleships HMS Warspite, HMS Ramilles and HMS Malaya, supported by the cruiser HMS Kent and three flotillas of destroyers bombarded Bardia harbour and Fort Capuzzo, starting at 06:45 and continuing for 22 minutes. As the vessels headed back towards Alexandria a series of bombing attacks were launched against them by the Regia Aeronautica.
The RAF and the FAA provided escort for the fleet. HMS Eagle's Fighter Flight of three Sea Gladiators had been flown to Sidi Barrani airfield in Libya, and from here patrolled over the Fleet. 'B' and 'C' Flights of 80 Squadron provided air support with flights of four Gladiators over the ships from dawn to dusk. ‘A’ Flight of 112 Squadron was positioned at Z Landing Ground (Matruh West) while ‘C’ Flight of 112 Squadron was based at Y LG about 18 kilometres further west and they also took part in the covering missions.
At 08:20, Flying Officer Peter Wykeham-Barnes and his three-aircraft section (Pilot Officer Stubbs as no.2 and Pilot Officer P. T. Dowding as no. 3) from ‘B’ flight of 80 Squadron took off on patrol over the fleet and climbed to 16,000 feet. At 09:10, they spotted a Cant Z.501 flying boat over Tobruk. The British pilots formed line astern and attacked from above and behind, using No. 1 Fighter attack. Wykeham-Barnes dived down through the clouds to attack it. As he was about to open fire his starboard gun came unmounted and ripped through the fuselage, severing a strut and damaging the leading edge of the tailplane. The Gladiator started to roll but he reacted quickly, put on full aileron to hold the mainplane and then continued the attack. It seems that Wykeham-Barnes had killed the gunner on the Italian flying boat since no more return fire was experienced. The three pilots made two passes each and the flying boat eventually fell in flames, crashed into the sea and sank immediately. The pilots returned to base at 10:00.
The Italian flying boat was a 143^a Squadriglia Z.501 from Menalao, flown by Sottotente Cesare Como with Sottotenente di Vascello Renzo Monselesan as observer that was shot down; the crew perished.

Stubbs ended the war with 1 shared biplane victory.

Claims:

Kill no.	Date	Time	Number	Type	Result	Plane type	Serial no.	Locality	Unit
	1940
	17/08/40	08:20-10:00	1/3	Z.501 (a)	Shared destroyed	Gladiator I	K7904	off Tobruk	80 Squadron

Biplane victories: 1 shared destroyed.
TOTAL: 1 shared destroyed.
(a) Z.510 from the 143^a Squadriglia Z.501 from Menalao, flown by Sottotente Cesare Como with Sottotenente di Vascello Renzo Monselesan as observer shot down with the loss of the crew.

Sources:
Desert Prelude: Early clashes June-November 1940 - Håkan Gustavsson and Ludovico Slongo, 2010 MMP books, ISBN 978-83-89450-52-4