Air Niugini is a Papua New Guinea airline and is smaller, offering flights to 39 destinations around Papua New Guinea, Asia, Oceania, and Australia. Top destinations include Brisbane, Guam, Hong Kong, Sydney, and Bali. Amenities depend on type of plane, but there is in flight entertainment on a TV, catering options for food, and full bar service.
Air Niugini's loyalty program is called the Destinations Loyalty Program and will give you additional checked baggage allowances as an Executive Club member. Carry on baggage and checked baggage requirements and regulations differ depending on your ticket class and route.