Air India - As in India, it is easy to get vegetarian food, but almost impossible to get vegan food. They normally carry extra vegetarian food. Air UK - Have vegan meals. Air Vanuatu - Seemed puzzled by the vegetarian meal request. American Airlines - Really good about vegetarian meals.
Every veggie meal comes with a packet of honey, and a cup of nuts and raisins.
British Airways - Good. Canadian - Vegan meals are great and never the same. Ask for vegetarian meals when booking or 24 hours before departure. Generally such a short flight that they only serve a rum punch. Good rum punch.