Did you know…
How heavy was the J.I's armor?
Short answer
The steel plate armor around the crew compartment weighed 490 kg (1,080 lb). The fuselage sides and bottom carried 5 mm chrome-nickel steel plate bolted directly to the wooden frame. That weight came at a substantial cost in performance.

490 kg of steel plate
The steel plate armor surrounding the Albatros J.I's crew compartment weighed 490 kg (1,080 lb) and came at a substantial cost in performance. The fuselage sides and bottom were covered with 5 mm thick chrome-nickel steel plate, bolted directly onto the wooden frame.
A new fuselage on familiar wings
In its overall layout, the J.I shared the wings and tail of the C.XII and adopted a new flat-sided fuselage, part-armored to protect its occupants from ground fire. Armament consisted of two fixed, downward-firing 7.92 mm (.312 in) Spandau LMG 08/15 machine guns, intended to strafe ground targets.
The price in performance
The J.I was fitted with the Benz Bz.IV engine, delivering up to 150 kW (200 hp); that powerplant, combined with a considerably heavier fuselage, was chiefly responsible for performance that was marginal at best. Luftstreitkräfte units began receiving the J.I during April 1918. By June 1918 the new Albatros J.II had begun replacing it at the front.
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