Earlier this month, Southwest Airlines initiated RNP operations following a $175 million investment that will eventually see its entire fleet flying with RNP by the end of 2013. For the first part of the transition of its fleet to RNP operations, Southwest is changing the pilot's view from the flight deck of its 737-700s. RNP or Required Navigation Performance allows aircraft to fly more precise tailored paths between two points, enabling faster routes to cut flight times, noise, fuel consumption and carbon emissions.
Before transitioning to RNP, Southwest's 737-700s were set up so pilots would see the Electronic Flight Instrument System (EFIS/MAP) format gauges (top) placing the the attitude indicator, HSI, DME, airspeed indicator, altimeter and vertical speed indicator in the same location as the carrier's older 737-300s. Boeing provided this layout as an option to airlines to duplicate the functionality of the Classic 737 flight deck for the Next Generation variants. Southwest's EFIS/MAP format is now being replaced through a software change with the large format Primary Flight Display and Navigation Display (PFD/ND) to render the precision RNP approach and departure paths.
The PFD combines the individual features of the EFIS into a single integrated display with a speed tape to the left, altitude and vertical speed indicator to the right, compass at the bottom and brown and blue attitude indicator at the center, similar to the layout on the 777 and 747-400 and -8.
During its transition to the new displays, the airline has opted to keep the side-by-side format for the Common Display System (CDS) Engine Instrumentation and Crew Alerting System (EICAS) (left), displaying all relevant engine data on the same level as the navigation data. Again, this format was created to mirror the same geographical locations as the gauges on the 737-300 to maintain commonality with the Next Generation models. The "over-under" format was designed to mirror the 777's engine displays, by placing the 737's secondary engine gauges on the lower EICAS screen.
Additionally, the airline's 737-300s will be getting an even more extreme makeover for the RNP transition, starting with the installation of 15.4in LCD displays to replace the steam gauges analog dial gauges. The first -300s with the new large-screen displays are expected to enter the fleet in early 2011.
A very special thank you to the Southwest Airlines pilot who supplied these before and after photos from the front office aboard two Boeing 737-700 aircraft.