Ahern Shipping Ltd.
The company was located in Montreal. The house flag was a swallowtail pennant, vertically divided into white and blue. A red throughout A was superimposing both stripes.
Source: US Navy Hydrographic Office: “Merchant Marine House Flags and Stack Insignia”, 1st edition 1961; p.3-8
Tthe flag indicates the company’s initial, "A", twice: by having an actual letter "A" on it and by having the ICS “alpha” flag pattern as its own background.