Swiss aeronautical engineer August Hafeli helped the German aero-concern of AGO Flugzeugwerke realize their C.I and C.II reconnaissance-minded biplanes in 1915 as World War 1 (1914-1918) raged across Europe. That same year, Eidgenoessische Konstruktionswerkstaette (K+W) was established in Switzerland and Hafeli was hired on to complete a similar project for the Swiss Air Force - beginning with the twin-boom "DH-1". This aircraft then spawned a series of similar designs for the country that included the DH-2 of 1916, DH-3 of 1917, and DH-4 of 1918 - these featuring a more conventional in-line design arrangement.
The DH-1 biplane would have reconnaissance as its central role and utilize a proven over-under biplane wing arrangement featuring three bays. Wood and fabric were used throughout its construction. The crewspace involved open-air cockpits seated along a centralized nacelle with booms stretching rearwards with each component capped by a small-area, rounded rudder plane. The booms were joined by a shared horizontal plane. The twin-wheeled undercarriage was fixed under the center mass with a basic skid added to the tail section for ground-running. The engine was installed at the aft-end of the fuselage component, completing the design arrangement of this aircraft. It carried a single machine gun of 7.45mm caliber for self-defense.
By and large, the DH-1 was similar in both form and function to Hafeli's earlier designs for AGO - highly conventional and no-nonsense.
The aircraft was powered by a single Argus As II series 6-xylinder, inline liquid-cooled piston engine outputting 120 horsepower and used to spin a two-bladed (fixed-pitch) wooden propeller. This powerplant was locally-built under license by Buhler Brothers Ltd. Since its placement was at the rear of the fuselage nacelle, the propeller arranged in a "pusher" configuration - this cleared the frontal vision and firing arcs of the aircraft for the observation crew.
Dimensions of the biplane included a running length of 28.10 feet, a wingspan of 42 feet, and a height of 9.9 feet. Performance included a maximum speed of 78 miles-per-hour, a range out to 160 miles, and a service ceiling of 32,280 feet.
Note: The above text is EXCLUSIVE to the site www.MilitaryFactory.com. It is the product of many hours of research and work made possible with the help of contributors, veterans, insiders, and topic specialists. If you happen upon this text anywhere else on the internet or in print, please let us know at MilitaryFactory AT gmail DOT com so that we may take appropriate action against the offender / offending site and continue to protect this original work.
(OPERATORS list includes past, present, and future operators when applicable)
✓Intelligence-Surveillance-Reconnaissance (ISR), Scout
Surveil ground targets / target areas to assess environmental threat levels, enemy strength, or enemy movement.
PUSHER-PROP
Design incorporates rear-facing pusher-prop arrangement, a contrast to the more conventional puller-prop layout.
MULTI-WINGED
Addition of more mainplanes to enhance inherent agility, providing a tactical edge in tight engagements.
RUGGED AIRFRAME
Inherent ability of airframe to take considerable damage.
HIGH-ALTITUDE PERFORMANCE
Can reach and operate at higher altitudes than average aircraft of its time.
EXTENDED RANGE PERFORMANCE
Capability to travel considerable distances through onboard fuel stores.
BAILOUT PROCESS
Manual process of allowing its pilot and / or crew to exit in the event of an airborne emergency.
CREW-MANAGED
Beyond a pilot, the aircraft takes advantage of additional crew specialized in specific functions aboard the aircraft.
GUN POSITIONS
Defensive gun positions for engagement / suppression.
Length
28.9 ft (8.82 m)
Width/Span
42.0 ft (12.80 m)
Height
9.8 ft (3.00 m)
Empty Wgt
1,653 lb (750 kg)
MTOW
2,480 lb (1,125 kg)
Wgt Diff
+827 lb (+375 kg)
(Showcased structural values pertain to the base Hafeli DH-1 production variant)
biplane / over-under / straight
Biplane
Design utilizes a dual-plane wing arrangement in which one mainplane member is seated above the other; biplanes enhance agility at the expense of added drag.
Over-Under
Dual mainplane configuration seating the members in an over-under fashion and poisitoned at different points along the fuselage.
Straight
The planform involves use of basic, straight mainplane members.
(Structural descriptors pertain to the base Hafeli DH-1 production variant)
Installed:
1 x Argus As II 6-cylinder, water-cooled inline piston engine developing 120 horsepower driving two-bladed wooden propeller in pusher arrangement.
(Showcased performance specifications pertain to the base Hafeli DH-1 production variant. Performance specifications showcased above are subject to environmental factors as well as aircraft configuration. Estimates are made when Real Data not available. Compare this aircraft entry against any other in our database or View aircraft by powerplant type)
1 x 7.45mm machine gun on trainable mounting in forward cockpit (managed by the observer).
Supported Types
(Not all ordnance types may be represented in the showcase above)
Hardpoint Mountings: 0
Ribbon graphics not necessarily indicative of actual historical campaign ribbons. Ribbons are clickable to their respective aerial campaigns / operations / aviation periods.
Images Gallery
1 / 1
Image from the Swiss Federal Archives; Public Domain.
Similar Aircraft
Aviation developments of similar form and function, or related to, the Hafeli DH-1...
The "Military Factory" name and MilitaryFactory.com logo are registered ® U.S. trademarks protected by all applicable domestic and international intellectual property laws. All written content, illustrations, and photography are unique to this website (unless where indicated) and not for reuse/reproduction in any form. Material presented throughout this website is for historical and entertainment value only and should not to be construed as usable for hardware restoration, maintenance, or general operation. We do not sell any of the items showcased on this site. Please direct all other inquiries to militaryfactory AT gmail.com.