As members of P/O Jack Phillis's crew, the then Sgt. Searson and Shortt were posted to 419 squadron on the 25th of May 1944
The other crew members were F/S Jack A. Phillis pilot, Sgt. James Norman RAF as F/E, F/S W. H. Devine Navigator, Sgt. Richard MacKinnon Bomb Aimer, and Sgt. Jack Spevak WAG. They had completed their training at No. 82 OTU followed by conversion training at No.1666 CU.

First Operation –First Combat

June 6th they were homeward bound from Coutances at only 3,000 feet the rear gunner Sgt. Shortt observed a FW190 astern and below the Lancaster and called for a corkscrew to starboard, while Sgt. Searson scanned the dark section of the sky for any additional attackers, Shortt fired off 200 rounds defending the Lancaster. The fighter had closed into 200 yards of the bomber before breaking away to starboard quarter. No fire was detected from the fighter and no damage was found on the Lancaster.

Second Operation – Second Combat

The crews very next operation on the following night, June 7/8 ,would bring them into combat again with one of the Luftwaffe’s Ju88 night fighter . Having arrived after over the target of Acheres at 01:25 hours and beginning their bombing run at 4,800 feet with an airspeed of 175 mph the Lancaster and crew were attacked at this point by the Ju88. Both young gunners spotted the enemy aircraft on the port quarter up at a range of 400 yards, rear gunner Sgt. Shortt gave the combat manoeuvre command, while continuing to fire at the Ju88 right up until it broke off the attack at 150 yards. Tracer had been seen to enter fighter’s cockpit, at which point the fighter broke off the attack disappearing off the starboard quarter up. Their Lancaster had escaped damage but a claim was put in for the fighter as "Damaged". Sgt. Shortt, who was just 20 had fired off 400 rounds at his adversary and claimed a "Damaged" on his second operation.

July 4th – Villeneuve St. George

By far the largest number of Combat Reports filed by 419 squadron would be on July 4th 1944 . And once again the gunners of Phillis’s crew would be active in driving off fighters from their aircraft.
The First Attack – 0038 Hours

As Lancaster VR-O neared it's target of Villeneuve St. George the rear gunner Sgt. Shortt saw a Ju88 shoot down another Aircraft then turn towards his bomber, coming down on the port quarter up at a range of 600 yards. He gave the corkscrew order and Phillis put the Lancaster into a corkscrew to port. The enemy fighter had started firing from 500 yards and followed the Lancaster through it's evasive manoeuvres and finally departed on the port beam up. Shortt had opened up on the Ju88 as it drew into 400 yards, firing off a burst 100 rounds and Sgt. Searson fired off a shorter burst of 50 rounds both gunners ceased firing when the fighter broke off the attack at 200 yards.
The Lancaster resumed course, but the bomber had sustained damage to starboard engine, starboard fuel tank, as well as damage to the fuselage, tail plane, wings bomb doors and undercarriage. During the action they had fallen 600 feet and recorded as having observed rockets, flak and fighter flares plus three other attacks against Halifax aircraft in the wave.
The Second Attack – 0050 Hours

With in minutes of the first attack another unidentified fighter was spotted by Sgt. Searson coming out of the light side of the sky on the starboard quarter above at a range of 500 yards.
The Lancaster again corkscrewed, but this time to starboard, Shortt in the rear turret opened fire until his guns jammed. The enemy fighter broke off the attack at 200 yards leaving by the starboard beam up. Which was fortunate as the rear guns could not be cleared
The crew were now defenceless from the rear, flying in a damaged aircraft with one engine out. With only upper gunner Sgt. Searson to protect them any attack from the rear. With all they had seen, one Halifax go down and others being attacked. It must have been a tense and long journey home.

July 24/25 1944 – Stuttgart

The night of July 24/25 would be the crews tenth operation together, this time to Stuttgart. The only information on what happened to crew and aircraft was given by Phillis a number of years later. He stated that the Lancaster was near Luxembourg when it was hit with a rocket, the aircraft caught fire and he ordered the crew to abandon the aircraft.
Before the command could be carried out the control of the aircraft was lost. Escaping from the hatches was difficult because of the actions of the aircraft as it spun down to earth. Devine was able to pull himself out of the aircraft. Devine, Phillis and MacKinnon were the only ones to get out. The aircraft came down 1 km south east of Bass, 16 km northeast of Vitry le Francais.
Both Sgt. John Searson (age 20) and Sgt. John Shortt (age 19) are buried in the cemetery of Bassu, Marne, France