Pictured are three Fairey IIIF floatplanes of No. 47 Squadron on the Blue Nile at Khartoum before departing for a series of exploratory flights over Southern Sudan on 8 July 1930. The aircraft pictured are J9796, J9809, and J9802.
As noted by RAF, who released the image as part of their 100 years of the RAF celebration in 2018:
The Fairey Aviation Company Fairey III was a family of British reconnaissance biplanes that enjoyed a very long production and service history in both landplane and seaplane variants. The RAF used the IIIF to equip general-purpose squadrons in Egypt, Sudan, Aden, and Jordan, where its ability to operate from both wheels and floats proved useful, while the contemporary Westland Wapiti carried out similar roles in Iraq and India. As such IIIFs were used for colonial policing as well as taking part in further long-distance flights.
The RAF also used the IIIF to finally replace the Airco DH.9A in the home-based Day-Bomber role, and, in the absence of sufficient long-range flying boats for maritime patrol duties by 202 Squadron from Hal Far Malta.
The IIIF remained in front line service well into the 1930s, with the last front-line RAF squadron, 202 Squadron, re-equipping with Supermarine Scapas in August 1935, and the final front line Fleet Air Arm squadron, 822 Squadron retained the IIIF until 1936.
Founded in 1916 to protect Hull and East Yorkshire against attack by German Zeppelins, No. 47 Squadron of the Royal Air Force today operates the Lockheed C-130 Hercules transports from RAF Brize Norton.
Not very many 104-year-old squadrons around these days.
Appropriately for the image above, their motto is Nili nomen roboris omen (The name of the Nile is an omen of our strength)