Frank Piasecki, 88; pioneered the tandem-rotor helicopter

Frank Piasecki, next to the XHRP-X, the first successful tandem helicopter in the world. (piasecki aircraft corp. file 1945)

WASHINGTON - Frank Piasecki, an engineer who flew the second successful helicopter in America and built the first technically and commercially viable tandem-rotor helicopter, died Feb. 11 at his home in Havertown, Pa., after strokes. He was 88.

Mr. Piasecki ranked with Igor Sikorsky and Arthur Young as a major helicopter visionary of the last century. His most significant contribution was creating, in 1945, a helicopter with one rotor each in the front and back, which could carry three times the weight of conventional helicopters.

His work helped extend the helicopter's use beyond aerial observation into combat, commercial, and rescue applications.

Roger Connor, curator of vertical flight at the National Air and Space Museum, said Mr. Piasecki's tandem-rotor design was significant because single-rotor designs "had trouble carrying weight of any size because the engine was under the rotor system."

"Adding cargo would unbalance the aircraft and take it off the center of gravity," he said.

Mr. Piasecki's tandem-rotor helicopter could "handle large cargo and a shift in weight without difficulty," Connor said. "It greatly increased capability at a time the military was beginning to look at that."

Mr. Piasecki and Sikorsky were at the forefront of their industry and competed to address problems with carrying ever-larger cargo loads. Mr. Piasecki's designs were first used operationally by the Navy in the early 1950s, but were not deployed to Korea during the war there.

Connor said Mr. Piasecki persuaded the French to use a second generation of Piasecki helicopters, the H-21 series, during the Algerian war during the 1950s.

From the successes and failures in Algeria, Mr. Piasecki was better able to refine the aircraft for the US Army and Air Force in the Vietnam War. He continued over the decades to make helicopters compatible with military needs, such as avoiding radar detection and landing in harsh conditions.

Technologies from his early designs led to later development of the Army's Chinook and Navy's Sea Knight, both of which are still in use.

Frank Nicholas Piasecki, whose father was a Polish immigrant, was born in Philadelphia.

As a teenager, he worked at two local companies making autogyros, a precursor to the helicopter. Many may recall the autogyro for its memorable appearance in two popular films of the early 1930s, "International House" with W.C. Fields and "It Happened One Night" with Clark Gable.

Piasecki was a 1940 aeronautical engineering graduate of New York University and that same year cofounded a company, P-V Engineering Forum, near Philadelphia.

He chose the name, he told The New York Times, "because if you used the word helicopter, people thought you were absolutely nuts."

He built his earliest helicopter models from parts he found in an auto junkyard near Philadelphia, and in 1943 followed Sikorsky as the second American to successfully fly a helicopter, the single-rotor PV-2.

Mr. Piasecki did not have an airplane license, and an awkward moment ensued as he prepared to test the PV-2 for military dignitaries at National Airport. A licensing official with the civil aviation agency asked for his airplane pilot's license, and he did not have one.

As a result, Mr. Piasecki received the first helicopter license, Connor said.

In 1945, Mr. Piasecki developed the first tandem-rotor helicopter, and it was soon put into production by the Navy. It was affectionately known as the "flying banana" for its bent fuselage, which keeps the rotors from hitting each other.

In 1960, Boeing bought one of Mr. Piasecki's successor businesses, Piasecki Aircraft Corp., and he continued to work in research and development.

One of his notorious failures was the Heli-Stat, a 343-foot-long airship made from a helium blimp and four surplus Sikorsky helicopters. It was designed for the US Forest Service to help with timber harvesting in remote areas.

His Heli-Stat project ended in disaster when it crashed in 1986 at the New Jersey airfield where the Hindenburg dirigible exploded in 1937. A pilot was killed, and three others were seriously injured.

Mr. Piasecki was a revered figure to many helicopter enthusiasts. He received the National Medal of Technology, the country's highest honor for technological achievement, as well as the National Air and Space Museum's lifetime achievement award. He also was inducted into the National Aviation Hall of Fame.

He leaves his wife, Vivian Weyerhaeuser Piasecki of Havertown; seven children; and 13 grandchildren.