The phrase "auxiliary engine" is correct and usable in written English.
It can be used in contexts related to machinery, vehicles, or maritime operations where a secondary engine is employed to provide additional power or support.
Example: "The ship's auxiliary engine kicked in when the main engine failed, allowing us to navigate safely to shore."
Alternatives: "backup engine" or "secondary engine".
After drifting for 3 days, engineers managed to start the auxiliary engine, and the ship is now limping back to its home port of Hobart, Tasmania.
Her air pumps were worked by an auxiliary engine, to which also the feed-pumps and bilge-pumps were attached.
It is probable that to this auxiliary engine was due the prolonged safety of the vessel -- that she would have foundered before the brig came alongside had the ordinary style of pumping been employed.
Two marine applications are examined using the model: (a) a scavenge air cooler, and (b) an auxiliary engine exhaust gas duct section integrated with thermoelectric generators.
In turn, we use auxiliary engine emission factors to estimate particulate matter and nitrogen oxide emissions from ships at berth, to determine how the corresponding damage costs of air pollution vary with container throughput, location, and terminal investments.
He saw a career in dentistry as another way -- an auxiliary engine -- to drive his passion for studying birds.
This equipment, along with smaller auxiliary engines, can emit dangerous levels of sulfur dioxide.
Most sailplanes are towed to launch altitude, although some employ small, retractable auxiliary engines.
As befits a modern working research vessel, she will have diesel auxiliary engines, radar, GPS navigation, satellite communications and modern safety equipment.
Most dhow traffic has been supplanted by larger, powered ships and by land transport, and the remaining dhows have been equipped with auxiliary engines.
Throughout Sunday, the submarine tried to move on its own power, twice starting its auxiliary engines, but by late afternoon, the ship was taken under tow by one of the three Soviet merchant ships that had come to the rescue.
