The Hampden Mk I had a pilot, navigator/bomb aimer, radio operator and rear gunner.
Conceived as a fast, manoeuvrable "fighting bomber", the Hampden had a fixed forward-firing .303 in (7.7 mm) Browning machine gun in the upper part of the fuselage nose.
To avoid the weight penalties of powered turrets, the Hampden had a curved Perspex nose fitted with a manual .303 in (7.7 mm) Vickers K machine gun and a .303 in (7.7 mm) Vickers K installation in the rear upper and lower positions.
The layout was similar to the all-guns-forward cockpits introduced about the same time in Luftwaffe medium bombers, notably the Dornier Do 17.
During the Norwegian Campaign, these guns proved to be thoroughly inadequate for self-defence in daylight; the single guns were replaced by twin Vickers K guns, a process led by Air Vice Marshal Arthur Harris of No.
5 Group RAF in 1940.

The Hampden had a flush-rivetted stressed skin, reinforced with a mixture of bent and extruded sections in an all-metal monocoque design.
A split-assembly construction technique was employed: sections were prefabricated and then joined, to enable rapid and economic manufacture.
The fuselage was in three big sections – front, centre and rear – that were built using jigs.
The centre and rear sections were made of two halves, which meant that the sections could be fitted out in part under better working conditions prior to assembly.
All possible assembly work was performed at the benches prior to installation upon each aircraft.

The wings were made up of three large units: centre section, port outer wing and starboard outer wing, which were also subdivided.
Each section was built around a main girder spar, leading edge section and trailing edge section.
The wing made use of wingtip slots and hydraulically-actuated trailing edge flaps; the flaps and ailerons had stress-bearing D-spars.
According to Moyes, the configuration of the wing was a key feature of Hampden, being highly tapered and designed to exert low levels of drag; these attributes were responsible for the aircraft's high top speed for the era of 265 mph (230 kn; 426 km/h) while retaining a reasonably low landing speed of 73 mph (63 kn; 117 km/h).

The Hampden's flying qualities were typically described as being favourable; Moyes described it as being "extraordinarily mobile on the controls".
Pilots were provided with a high level of external visibility, assisting the execution of steep turns and other manoeuvres.
The control layout required some familiarisation, as some elements such as the hydraulic controls were unobtrusive and unintuitive.
Upon introduction, the Hampden exhibited greater speeds and initial climb rates than any of its contemporaries while still retaining favourable handling qualities.

The slim and compact fuselage of the aircraft was quite cramped, being wide enough only for a single person.
The navigator sat behind the pilot and access in the cockpit required folding down the seats.
Once in place, the crew had almost no room to move and were typically uncomfortable during long missions.
Aircrews referred to the Hampden by various nicknames due to this, such as Flying Suitcase, Panhandle, and Flying Tadpole.

I did my first flight and first tour on Hampdens.
A beautiful aeroplane to fly, terrible to fly in!
Cramped, no heat, no facilities where you could relieve yourself.
You got in there and you were stuck there.
The aeroplane was like a fighter.
It was only 3 feet wide on the outside of the fuselage and the pilot was a very busy person.
There were 111 items for the pilot to take care of because on the original aircraft he had not only to find the instruments, the engine and all that, but also he had all the bomb switches to hold the bombs.

— Wilfred John 'Mike' Lewis
The Hampden Mk I had a pilot, navigator/bomb aimer, radio operator and rear gunner. Conceived as a fast, manoeuvrable "fighting bomber", the Hampden had a fixed forward-firing .303 in (7.7 mm) Browning machine gun in the upper part of the fuselage nose. To avoid the weight penalties of powered turrets, the Hampden had a curved Perspex nose fitted with a manual .303 in (7.7 mm) Vickers K machine gun and a .303 in (7.7 mm) Vickers K installation in the rear upper and lower positions. The layout was similar to the all-guns-forward cockpits introduced about the same time in Luftwaffe medium bombers, notably the Dornier Do 17. During the Norwegian Campaign, these guns proved to be thoroughly inadequate for self-defence in daylight; the single guns were replaced by twin Vickers K guns, a process led by Air Vice Marshal Arthur Harris of No. 5 Group RAF in 1940.
The Hampden had a flush-rivetted stressed skin, reinforced with a mixture of bent and extruded sections in an all-metal monocoque design. A split-assembly construction technique was employed: sections were prefabricated and then joined, to enable rapid and economic manufacture. The fuselage was in three big sections – front, centre and rear – that were built using jigs. The centre and rear sections were made of two halves, which meant that the sections could be fitted out in part under better working conditions prior to assembly. All possible assembly work was performed at the benches prior to installation upon each aircraft.
The wings were made up of three large units: centre section, port outer wing and starboard outer wing, which were also subdivided. Each section was built around a main girder spar, leading edge section and trailing edge section. The wing made use of wingtip slots and hydraulically-actuated trailing edge flaps; the flaps and ailerons had stress-bearing D-spars. According to Moyes, the configuration of the wing was a key feature of Hampden, being highly tapered and designed to exert low levels of drag; these attributes were responsible for the aircraft's high top speed for the era of 265 mph (230 kn; 426 km/h) while retaining a reasonably low landing speed of 73 mph (63 kn; 117 km/h).
The Hampden's flying qualities were typically described as being favourable; Moyes described it as being "extraordinarily mobile on the controls". Pilots were provided with a high level of external visibility, assisting the execution of steep turns and other manoeuvres. The control layout required some familiarisation, as some elements such as the hydraulic controls were unobtrusive and unintuitive. Upon introduction, the Hampden exhibited greater speeds and initial climb rates than any of its contemporaries while still retaining favourable handling qualities.
The slim and compact fuselage of the aircraft was quite cramped, being wide enough only for a single person. The navigator sat behind the pilot and access in the cockpit required folding down the seats. Once in place, the crew had almost no room to move and were typically uncomfortable during long missions. Aircrews referred to the Hampden by various nicknames due to this, such as Flying Suitcase, Panhandle, and Flying Tadpole.
I did my first flight and first tour on Hampdens. A beautiful aeroplane to fly, terrible to fly in! Cramped, no heat, no facilities where you could relieve yourself. You got in there and you were stuck there. The aeroplane was like a fighter. It was only 3 feet wide on the outside of the fuselage and the pilot was a very busy person. There were 111 items for the pilot to take care of because on the original aircraft he had not only to find the instruments, the engine and all that, but also he had all the bomb switches to hold the bombs.
— Wilfred John 'Mike' Lewis
Handley Page Hampden