There has been a lot of speculation regarding Southwest getting another aircraft type, most centered around a larger regional jet. And Parker said they were actually considering the idea of a smaller aircraft(but probably not seriously yet).
However, there is one kind of smaller aircraft that could open new, smaller markets for Southwest. It is especially well suited for high-frequency shorthaul flights, and is more efficient than its competition on these routes. Its breakeven load factors tend to be comparatively low. Routes that it competes on are often high fare and have far less traffic than they could if properly exploited. For just about every airline in the US, these planes are slaves to the hub spoke system and are not used to nearly their full potential. It is available at very low prices, for it is not very popular at the moment in the US.
This aircraft is the turboprop. The modern, 70 seat turboprop could be a good way for Southwest to expand to new markets. The business market would not need to change all that much, it would just be extended to smaller cities with the new aircraft. Southwest would pick out cities like Wichita and fly the Q400 to say, Denver, Kansas City, and maybe one other city. Just like with the 737's, the trick is to go into a city, fly point to point to its neighbors, and get people out of their cars with low fares.
On the REVENUE side.....People will fly turboprops rather than drive if the price is right, we see this in how they use turboprops to connect to hubs in other cities. And people who usually drive will not be put off by seeing a turboprop rather than a jet, especially if it is a modern 70-seater. In fact, a lot of people unconsciously think of a jet as any airliner that can be boarded with a jetbridge or is big enough to have a flight attendant. The Southwest name and its customary new-city advertising would do a lot to attract traffic. Also, many routes that are currently served only by regional jets or props are high-priced from the point of view of the point-to-point traveler. The airlines just do not think about this market very much, and when they do, they think that only high-paying business travelers would be interested. For example - currently the fare from Springfield, Illinois to Chicago is often around $150 roundtrip, even with the supposedly low-cost ATA in the market(it was even higher before). Cut that price in half and you could have enough traffic to fill several Dash 8 flights, and make money doing it.
On the COST side.....Q400's are more fuel efficient than jets on shorthauls, which is how they would be used, mainly. They are available for very low prices and at good terms. The cost of using these planes is even lower when you account for the fact that most airlines under-utilize them in order to accommodate hub schedules. Give them 12 hours a day and they look even better. They are also less demanding of airport facilities. The big question mark is in labor costs and agreements......
One of the main factors that may eventually limit Southwest's expansion is its preference for at least 10-12 flights for each city right from the start. Many, many more cities could support 10-12 dash-8 flights. It would take far fewer aircraft to provide them if they were traditional Southwest shorthauls than if these flights were RJ
style runs to "hubs" like BWI
The dash-8 could complement the 737. Cities could have about a dozen dash-8 flights and maybe a 737 or two to a more distant or popular destination. Dash-8's could be used for some less popular runs at or between major bases.
SHORT- the advantages of the dash 8 versus the regional jet....
1. Better suited to Southwest's core, original business model.
2. Lower acquisition, fuel, and facilities cost - leading to a lower breakeven
3. Many overpriced and underserved routes could be more easily opened with
props than jets.
4. They allow service to a wider variety of cities, both because the demand less from airports and because they have lower costs.
The main disadvantage, as I see it, is a potential labor cost disadvantage and/or labor strife. But regional jets would suffer from the same thing........