Brake

If planes could brake themselves on the air and alight as abruptly as birds do by reversing the thrust that gives them flight, aviation would be vastly safer and more convenient. To this end, Inventor C. Francis Jenkins of Washington, D. C., radio and television expert, has been applying himself lately to discover a literal "air brake." Last week he announced success.

Mr. Jenkins' invention did not, however, enable a plane to depress its wings, bird fashion. It was an adaptation of the reversible propeller blade already used on water ships but hitherto considered too dangerous for planes because of the havoc a pilot would cause by pulling his reversing lever at the wrong moment. The Jenkins device included a safety catch released only by the contact of the plane with its landing surface. When this catch releases, the pilot can "shift gears," reversing the pitch of his propeller blades so that the pressure they beat up pushes the plane backward instead of forward. If reliable, the Jenkins invention promised to be even more effective than the wheel brakes already in use on land planes. Wheel brakes can be thrown out of commission by a heavy landing. The reversible-blade brake will function as long as the motor runs.