Alex Henshaw apparently did it regularly using the plume of smoke from the factory
Used in an operation flying home from oil rigs offshore, hot air from the gas plant next door to home would cause a localised bump in the top of the undercast, no approach aids, we were VFR after all.
Military ground school instructor told of his days flying DC-3 in Sth. America, airport, an all over field, frequently the subject of fog but steeple of church always protruded, over the steeple at certain altitude and heading and let down at certain rate till the wheels made contact.