Sgt Kratke re-joined 317 Squadron on 8th April 1941 after a course at 56 OTU.
On 24th June, he finished his attachment to No.4 Delivery Flights.

On 21st February 1942, An invasion operation carried out by the army began with the intention of making a landing at Slapton Sands. Squadrons 247, 306, 307 and 317 being asked to co-operate with the enemy. In connection with this P/Os Kratke, and Zbrozek took off at 17.10 hours and Beat up Kingsbridge, Iverybridge and Dartmouth.

On 15th March 1942, instructions were received for the squadron accompanied by 306 Squadron to provide bomber escort to five bombers and to proceed towards the French coast in search of shipping.
Both squadron took off from Exeter at 15.40 hours and rendezvoused with bombers. The ships were seen about 5 to 10 miles from the French Coast in the vicinity of Tregastel but no attack was seen by our pilots owing to the state of the weather i.e. 10/10 cloud at 200 feet. At approx. 16.30 hours the fighters turned for home and when in the vicinity of Falmouth at 17.10 hours where the weather was the some as over the French Coast they steered course for Predannack where they intended to land. On arrival in the vicinity the cloud and mist being so low they searched for 15 minutes in an effort to find the drome, but without success.
It was decided to proceed to Bolthead although the pilots were now losing sight of the another owing to the poor visibility. On arrival in the vicinity conditions were very bad the drome being completely covered with thick cloud. In fact one pilot (F/O Koc), even with the aid of instruments flew over the drome at twenty feet but was unable to see it. The pilot although his gauge indicated that he had only seven gallons of fuel left decided to make for Exeter where he made a successful landing at 18.04 hours.
All aircraft were now very short of fuel the result was that they had to crash land in the vicinity of Bolthead. The only other successful landing was made by F/Sgt Brzeski at Newquay.
The remaining ten aircraft all crash landed in the Bolthead area. In the course of landing all ten aircraft were damaged six being Cat. E., four Cat. B.
The Squadron Commander, S/Ldr Brzezinski struck the side of a cliff and was killed instantly. Other casualities were F/Os Kratke and Hrycak slightly injured and admitted to R.A.F. Hospital Torquay.

On 31st July 1942, the Squadron was called upon to take part in a sweep over France as part of a diversion Wing. In mid-channel, two Focke Wulf 190’s came out of the sun and attacked, hitting (Flying Officer) Kratke's aircraft and setting it on fire. F/O Kratke baled out, and descended towards the channel as three aircraft from his squadron guarded him by flying in circles above him. On landing, his dinghy opened alright and he was seen sitting in it showing signs that he was alright, except for one of his legs was wounded.
One Section of 317 Squadron landed at Tangmere for re-fuelling and then went back to the Channel where they relieved the other Section who were still guarding over F/O Kratke.
He was eventually rescued by a boat, and admitted to the Naval Hospital, where he started two month's convalescence following his injuries.