I have to disagree with everyone.

70-140 seat: BAE-146/Avro RJ

Pretty cheap, easy to get on the used market, great size, lasts a decent amount of time. 

140-200 seat: McDonnell-Douglas MD-81/MD-83 and 737-800

Mad-Dog 80s: Cheap, easy to get used, range is bearable, but can match my airline's needs easily. On longer flights, I use 737-800s equipped with winglets.

200-260 Seat: Airbus A321-200

I very much like this plane when needing to fill passengers on a plane. Easily suites the needs of my airline, but I usually have to get them new.

260-350 Seat: Boeing 767-300ER

I got this plane when working at another airline. I don't usually buy planes of this size, as I rather operate more flights in smaller planes, but was defiantly a well rounded plane.

350+ Seat: Boeing 767-400ER, Airbus A340-500, and 747-400ER

The 767-400ER is a decent plane, uncommon, but can do decently long routes. The A340-500 is my choice of plane after 2002 for trans-pacific routes that are incredibly long. The 747-400ER packs passengers, not much can be said, but I love it.

Well, I do run an airline called PSA, but please stop joking about crashes.

PSA 87 begins push backing from SFO.

Lets do a different flight

PSA Flight 87 is at SFO waiting to depart for SAN. The MD-81 is packed to the gills, with happy crew and passengers on board.

Yes, but many planes were ordered before that.

I need the aircraft.

Besides that as that takes too long with the growing fleet.

Do you now how to quickly install winglets on over 100 737-800s? Thanks!

Hello, I am willing to take over your airline. I have DMed you my forum ID

They need to tell you.

To answer the Concorde Question, it isn't very viable. They are ever so slightly cheaper than an A340-300. These A340 have more range, and over 3 times the capacity. The planes are half as fast, so the Concorde can't make up the difference and isn't viable for most airlines.

Most Airlines in real life have 20 year old planes. I think you shouldn't go much farther than 25.

Use props on shorter flight. They are slower, but a whole lot cheaper.

In range there are two numbers, one is standard and one is max.

How do I get the max range.