The Airco DH.4 is a British two-seat biplane day bomber of the First World War. It was designed by Geoffrey de Havilland (hence "DH") for Airco, and was the first British two-seat light day-bomber capable of defending itself. It was designed and developed specifically as a bomber, as well as aerial reconnaissance missions.

Modeled from a combat-tested British De Havilland design, the DH-4 was the only U.S. built aircraft to see combat during World War I. With inadequate funding to buy new aircraft, the newly created U.S. Army Air Service continued to use the DH-4 in a number of roles during the lean years following the war.

Two-seat, single-engine World War I biplane observation and bomber aircraft; 400-horsepower Liberty V-12 water-cooled engine. American-built version of a British design. Fuselage light grey on sides, olive green on top. Performance. United States variants. DH-4 : Two-seat day bomber biplane, built in the United States.

Airco DH.4 是 第一次世界大战 的英国两座 双翼飞机 日轰炸机。 它是由 杰弗里·德·哈维兰（Geoffrey de Havilland ）（因此是“ DH”）为 Airco 设计的，是第一位能够捍卫自己的英国两座轻型日狂热者。 它是 专门为轰炸机 以及 航空侦察 任务设计和开发的。 DH.4将由新的160 hp（120 kW） Beardmore Halford Pullinger （bhp）发动机提供动力，但这导致了许多其他发动机，也许是最好的发动机，其中最好的是375 hp（280 kW） ） 劳斯莱斯鹰 引擎。 DH.4于1916年8月首 …

西线的英国皇家空军dh.4. 好了，言归正传，dh.4其实是一款英国战机，而且是第一款被设计为专用昼间轰炸机的飞机。其在西线表现优异，原因就在于驾驶员和观察手直接隔了很大一块距离（距离产生美）

1917年3月，英国制造的dh-4抵达西线，美国制造的改进版——dh-4s型，也于当年年底开始量产。 DH-4S型配备了超大功率的400马力“自由”发动机。 在俄亥俄州和新泽西州的三个大型飞机制造厂中，一共制造了不下4846架美同产DH-4。

22–24 February 1921: First Lieutenant William DeVoe Coney, Air Service, United States Army, flew across the North American continent with just a single fuel stop. His airplane was an Atlantic Aircraft Corporation DH-4M-2, a version of the Airco DH.4 designed in …

这是航空史上第一次空中加油试验，那第一架空中加油机的代号为DH─4M.这时的加油过程全由人力操作，加油机高于受油机，靠高度差加油。 这种加油方式很难实际应用。 40年代中期，英国研制出插头锥套式加油设备，1949年美国研制出伸缩管式加油设备，这才使空中加油进入了实用阶段。 空中加油机给飞行中的飞机及直升机补加燃料的飞机。 多由大型运输机或战略轰炸机改装而成 。 其作用可使受油机增大航程，延长续航时间 ，增加有效载重 ，以提高航空兵的作战能力。 …

2025年2月24日 · The Airco DH.4 was a very successful airplane of World War I, designed by Geoffrey de Havilland. The DH.4 (DH-4 in American service) was a two-place, single-engine, two-bay biplane with fixed landing gear. The fuselage and wings were constructed of wood and covered with doped fabric.

Constructed as a DH-4M-1. The only American Built DH-4 type specifically for non-military duty. From 26 September 1924 to 1927. To United States Postal Service, Washington, DC. Markings added: 489 Aircraft declared surplus in 1927. 1927. To United States Department of Agriculture, Washington, DC. Markings added: 489. 1927