Honeywell says it is working with the US Federal Aviation Administration "to understand the path to certification" of a combined synthetic and enhanced vision head-down display system that could be used to gain lower landing minimums in instrument flight conditions without a head-up display.

The company revealed last week that it has flown more than 25h of demonstration flights with combined systems on company-owned Cessna Citation V and Cessna Sovereign business jets as of early September.

Called SmartView, the system merges Honeywell's synthetic vision technology with enhanced vision equipment built by various vendors.

On the prototype system, which is being tested at Honeywell's rapid prototyping lab in Phoenix, Arixona, pilots see the camera image directly overlaid on a portion of the synthetic vision scene on the primary flight display. A toggle is available to change the transparency of the enhanced image with respect to the underlying 3D synthetic scene, which is based on terrain and obstacles data used by the company's enhanced ground proximity warning system.

The primary target market initially for such a "merged" system is the more than 450 business jets with enhanced vision systems and Honeywell's Primus Epic-based integrated avionics, says Sergio Cecutta, marketing manager for Honeywell's advance vision systems group. Most of those aircraft are also equipped with head-up displays, he adds.

Cecutta says the software-only merged vision upgrade for applicable Primus Epic-based platforms could be available in the 2011 or 2012 timeframe.

Honeywell's PlaneView avionics suite for Gulfstream features synthetic vision on the primary flight display and head-up enhanced vision using a Kollsman infrared camera. Dassault offers an enhanced vision system (EVS) built by CMC and will have synthetic vision available as part of its Primus Epic-based EASy avionics suite starting next year.

When equipped with a head-up display, FAA and European rules allow pilots to fly down to 100ft (30m) above the ground using augmented vision for straight-in precision and non-precision approaches, compared to 200ft or higher for most instrument approaches.

Cecutta says having the same capabilities for a head-down display on existing aircraft would allow the "pilot not flying", the crew member focused on the instrument panel, to have the same information as a pilot looking through the HUD during the approach, increasing situational awareness of the crew as a whole.

For forward fit applications, the capability could mean not having to buy head-up displays.

The company's presumption that the FAA will change flight rules in favour of lower landing minima using head-down displays could be premature however, as the agency has not yet determined whether the practice is viable from an operational and safety standpoint.

Source: Flight International