The de Havilland Canada DHC-7, popularly known as the Dash 7, is a turboprop-powered regional airliner with short take-off and landing (STOL) performance.

In the 1960s, de Havilland Canada was already well known worldwide for their series of high-performance STOL aircraft, notably the very popular DHC-2 Beaver and DHC-6 Twin Otter.

Changes included the addition of cabin pressurization (requiring a switch to a fuselage with a circular cross-section), landing gear that folded forward into the inner engine nacelles, and a large T-tail intended to keep the elevator clear of the propwash during take-off (the Twin Otter's empennage was a cruciform arrangement).

The Twin Otter incorporated "flaperons" that drooped the ailerons as part of the flaps, but these were not included in the Dash 7 due to weight and complexity.

Upon touchdown, both the inboard and outboard roll spoilers extend in unison to aid in destroying lift created by the wing.

During a typical STOL landing, flaps are selected to the 45° position, generating more lift and drag, thus allowing for steeper descents and lower approach speeds.

On touchdown, through "squat switches" in the main gear, the flaps automatically retract to the 25° position, thus reducing lift once on the runway and producing better braking performance.

The four-engine layout aids lift at low speeds due to the wide span of the propellers blowing air over the wing ("propwash").

The Dash 7 enabled Rocky Mountain Airways to operate scheduled passenger air service from Denver into the Avon STOLport in Colorado which was controlled by the airline.

Another close-in ski resort airfield served by Rocky Mountain Airways with Dash 7 flights from Denver was Steamboat Springs Airport in Colorado.

[4] The original Series 100 represents the vast majority of the aircraft delivered, and came in two models; the DHC-7-102 passenger version and -103 combi with an enlarged cargo door.

Most commuter airline turboprop operators used the aircraft as feeder liners into large airports, where the STOL performance was not considered important.

One exception to this was operations at London City Airport (LCY), which upon opening in 1987, was capable of handling few other aircraft types besides the Dash 7 due to its relatively short runway and steep approach.

These aircraft received the CF designation CC-132 and were delivered to 412 Transport Squadron at Canadian Forces Base Lahr, in West Germany.

[5] The United States Army operates several Dash 7 aircraft as surveillance platforms with the designation EO-5C (RC-7B before 2004)[6] under the Airborne Reconnaissance Low program.