Bomber Command Headquarters came to the conclusion that destroying the two aqueducts (codenamed M.25 & M.25A) was key to disrupting the movement of supplies (and later, the barges themselves) towards the proposed invasion ports.
'The 'Calendar of Raids' shows that there were at least 15 raids of varying strength against these targets.
This photograph is taken looking south with the original aqueduct on the left and the later 1930s bypass construction on the right.
A view through an arch of the old aqueduct looking towards the 1930s aqueduct.
This 'Then & Now' propaganda photograph is, I believe, incorrectly dated 18th July 1940 and shows the water drained from the 'bypass' channel (M.25A).
Damage can be seen to the canal bed and bank but with the aqueduct itself is undamaged.
There were several PDU (Photographic Development Unit) flights to record the results of raids but the date of this photograph does not follow a significant raid on the aqueduct.
The photograph is also overly optimistic as it fails to show the undamaged 'old' aqueduct (M.25) which has been cropped off the bottom of the image (see below).
The top of the picture is direction north west.
A determined attack on the 25-26th July by 18 Hampdens from 49 & 83Sqns damaged the new aqueduct (M.25A), but the canal was still open to barge traffic.
Given the number of bombs indicated, this and the 'Then & Now' image are likely to be photographs of the 25-26th July raid.
Following the failure to destroy either structure, Bomber Command decided on fresh tactics.
They would select and intensively train a number of crews to attack these specific targets.
It was decided to chose twelve Hampden crews from 49Sqn & 83Sqn.
These crews spent two weeks practising 'attacking' canals in Lincolnshire and many hours were spent examining plasticine models of the target area. Finally, five of the crews were chosen to attack the original stone aqueduct.
Note: Two of the 'overlooked' crews were to carry out a diversionary raid. On the night, these raids were flown by S/L Collier and Sgt Seal. Another crew not selected for the main attack was that of F/O Guy Gibson who was sent on leave. He returned to operations on the 24th August 1940.
The difficulty of the task, which was to take place at low level and at night, can be appreciated by the above image of the cramped pilot's position in the Hampden.
Flt Lt Learoyd's 49Sqn Hampden (P4403 EA-M) photographed at RAF Scampton
The Hampden was named ‘Pinocchio’ after the Walt Disney character painted just below the left side of the Hampden’s cockpit.
Some accounts of the raid say that Flt Lt Learoyd from 49 Sqn made a solo reconnaissance of the target area on the night of 11-12th August but the operational records of his squadron make no mention of this flight.
However, at around 21:00hrs on Monday 12th August eleven Hampdens (5 from 83Sqn and 6 from 49 Sqn) took off from their Scampton base.
A 49Sqn Hampden (EA-F) is bombed up at RAF Scampton
The five crews designated to attack the canal aqueducts in attack order were:
Sqn Ldr Pitcairn-Hill (83 Sqn)
F/O Ross (83 Sqn)
Flt Lt Mulligan (83 Sqn)
P/O Matthews (49 Sqn)
Flt Lt Learoyd (49 Sqn)
As the newer aqueduct (M.25A) was already damaged (but still operating) it was decided to concentrate the attack on the older structure (M.25).
The repairs of M.25A were well underway making the canal narrower but still usable. As the traffic was mostly in one direction - towards the ports - it is possibly debatable whether targetting a single aqueduct was the correct decision.
Each bank of the canal was heavily defended so that the attacker had no choice but to run the narrow gauntlet of anti-aircraft fire during his actual bombing attack.
The attacking force navigated to the south of the target and Sqn Ldr James Pitcairn-Hill, the first to attack, threaded his way northwards through a curtain of flak and blinding searchlights.
Levelling out at 100 feet above the canal he maintained a rock-steady bombing run and released his bombs before banking away from the danger zone. Although badly damaged by the intense light flak he limped home to England.
F/O Ellis Ross then began his descent to attack in the same manner but received a direct hit and crashed in a holocaust of flames alongside the canal.
The remains of the crew were recovered from the wreckage and buried close to the crashsite. Unfortunately, following very heavy raids later in the war, their graves were lost. The crew names are recorded on the Runnymede Memorial.
The third Hampden to attack was Flt Lt Mulligan who was hit repeatedly by intense light flak. In an attempt to climb out of trouble they jettisoned their bomb which fell into the canal some distance short of the target. Unable to gain sufficient height to bale out, F/L Mulligan looked for a suitable area in which to crash land. An opportunity appeared close to the village of Mesum and he made a violent forced landing in a large muddy field.
Unfortunately, Sgts Hill & Abel were killed and it took the Germans several hours to remove Flt Lt Mulligan from the mangled remains of his Hampden.
Flt Lt Mulligan and Sgt Younger became PoWs and Sgts Abel and Hill are now buried in the Reichswald War Cemetery.
P/O Matthews, with one engine immediately put out of action, pressed on through the intensifying flak and successfully dropped his bombs very near to the target.
Nursing his one remaining engine he managed to struggle back to base.
The remaining Hampden, piloted by Flt Lt Roderick 'Babe' Learoyd, now alone, faced the full intensity of the defences. With searchlights almost blinding him he flew along the canal at an altitude of 150 feet and tried to ignore the maelstrom of cannon shells and machine gun bullets.
His bomb-aimer concentrated intensely on the task in hand and dropped their 'M' bomb exactly on target. Learoyd immediately banked away from the target.
The 'M' bomb was a specially adapted naval mine which was slowed by a drogue parachute and was fitted with a delayed-action fuse (using soluble aspirin).
Image courtesy of DKW Auctions
His aircraft, M-Mother (P4403), was very badly damaged but both engines were still going strong. Learoyd made it back to Scampton where he circled until daylight. Even with severe hydraulic damage he managed to make a safe landing.
A short time later, in Air Ministry Orders No 256/1940 F/Lt 'Babe' Learoyd was awarded the Victoria Cross. This award was the first to be earned by Bomber Command in WW2.
Two days later a photo reconnaissance aircraft flew over the target area.
The bend in the River Ems identifies the target area and the damage to the old aqueduct (red circle) is clearly visible. Although the newer aqueduct was still open to traffic (yellow rectangle), the raid was hailed as a major success.
The 'old' aqueduct was badly damaged but it would take the German's less than two weeks to make a full repair. The 'bypass' aqueduct was unaffected by this raid but it is possible that the attack played its part in hindering the movement of war material to the invasion ports at a most critical point in the war.
Two images of the damaged aqueduct, the first showing water still flowing through the breach and the second, when the emergency gates had been closed.
Images courtesy of Herbert Ründe and the Heimatverein-Graven.
A German police helicopter pilot's view of the aqueduct looking in the direction of the attack.......image courtesy of Herbert Ründe.
Access to the site today is straightforward although investigators should be warned that this is now an area for nude sunbathing.
Anyone exploring the location with a camera should be aware of this!
Today, the repairs (done with concrete) to the damage caused in August 1940 can easily be seen on the side of the old aqueduct.
The old aqueduct is no longer used and the stretches of canal on either side have been left as a nature reserve or have been filled in.
The actual aqueduct itself has been left drained but otherwise is unchanged.
The emergency "water stop" gates on both sides of the aqueduct are in the closed position.