To support its mission of simulating any aerospace vehicle, the VMS simulates all types of instruments, from the older dial-type (analog) instruments to the most modern electronic (digital) displays. Analog instruments at the VMS can be modified as needed, and electronic instruments can be programmed to display information in numerous ways. Researchers frequently request that flight instruments still in the design stage be simulated for testing.
Among the hundreds of flight instruments at the VMS are these analog instruments. From left to right are a sliding tape display, a dial, a compass, and a spherical attitude direction indicator.
Sliding Tape Display
Dial
Compass
Altitude Direction Indicator
Electronic instruments provide great flexibility because they display information on cathode ray tubes (CRTs), like those found in most televisions and computer monitors. The computers that drive them can be programmed to display information as needed. Besides presenting text and numbers, CRTs display symbology: graphics that represent information. This symbology can either simulate analog flight instruments or present information in new ways.
Electronic Instrument Display
The symbology representing a compass at the bottom of this electronic instrument is an example of the simulation of an analog instrument. The diamond-shaped symbology at the very center of the instrument presents guidance information information that helps direct the pilot that was not possible before electronic displays. Other symbology shown here simulates a needle-type instrument and two sliding-tape displays with magnifying lenses.
Another type of electronic display is a head-up display (HUD). A HUD projects vital information onto a glass pane, called a combiner, which is positioned between the pilot's eyes and the window. In this way, the pilot has less need to look away from the window and down at the instrument panel. HUDs can be useful during any phase of flight, but they are especially important during critical maneuvers, when they provide an extra margin of safety. This HUD displays guidance information for a pilot making a landing in fog.
HUD as seen from the interior of an ICAB cockpit
HUD Diagram
This diagram shows one type of HUD. Because a CRT is used to project the image, a HUD can be programmed to display information in various formats.
One more type of electronic display is a helmet-mounted display (HMD). The photograph on the left shows a small CRT and combiner mounted on the pilots helmet. The combiner is like one lens of a pair of glasses; the pilot would see the symbology on the right reflected in it, in addition to whatever the pilot was looking at. One advantage of an HMD is that the display remains in the pilots view regardless of the direction in which the pilot is looking. An HMD can also be used for sighting weapons.
Helmet-Mounted Display (HMD)
HMD Diagram
The VMS demonstrates exceptional flexibility in the simulation of flight instruments. The ability to modify analog instruments and to customize electronic displays enables the simulation of virtually any existing instrument, as well as instruments in the design stage. The accurate delivery of information via flight instruments is one important part of real-time simulation at the VMS.