Government and industry players are doing quick advancement in ushering in the age of "equivalent visual operations" for airlines and air taxis that uses hardware and software which provides pilots what the human eye can’t which is a weather-free view of the earth further than the windscreen all the way to landing the airplane and transporting to the gate.

Business Aviation Outlook

Business aviation had already taken the early upper hand in launching such technologies in the USA, with Gulfstream and Bombardier both acquiring credits for lower instrument landing minima which can be found in Part 91 general aviation rules using improved vision systems and head-up displays to enhance eye contact with the runway environment in 2001 and 2005, respectively.

But modifications in policies in Europe and probable arrangements with US Federal Aviation Administration regulations will soon make the improvements obtainable to airline and charter cockpits also.

The European Aviation Safety Agency (EASA) in August 2008 made changes in its rules (EU-Ops rule 1.430(h)) to let properly trained crews and aircraft that has a certificated enhanced flight vision system (EFVS) to lessen the mandatory minimum visibility necessary to begin an instrument approach by around 33%. Once on the approach, the pilots are then authorized to use the EFVS in place of normal vision down to a 100ft (30m) decision height for a category 1 approach, down from the usual 200ft decision height.

Normal Vision

Below 100ft, pilots need to utilize their natural vision to recognize the runway surroundings to carry on the approach to landing.

Not like a comparable FAA universal aviation regulation (FAR 91.175) however, the European rule is applicable to charter and airline operations adding up to general aviation (Part 91). In the USA, there is still an "approach ban" that is not allowing airline (Part 121) and air taxi (Part 135) pilots to start an approach if announced flight visibility is lower than the least published for the approach.

Category 1 instrument approaches currently require 0.5nm flight visibility or 1,800ft "runway visual range".

Reduced landing minima is the initial stage in the wider push by the FAA and Europeans to sooner or later use improved flight visual systems all the way to touchdown. The system could in turn enhance capacity in instrument weather whilst letting aviation authorities to save cash by not needing to install instrument landing systems and the related lighting infrastructure at great number of airports and runways.

The last two years have witnessed a number of "walk before you run" efforts in developing equivalent visual operations (EVO), an answer for the US next generation air transport system (Nextgen) objective of growing capacity and safety with fewer ground infrastructure. By looking on the advancement made in 2009, 2010 must prove to be a breakthrough time for FAA Part 121 and Part 135 operators.


A logistics services company FedEx Express and fractional private business jet charter and aircraft management company NetJets are leading the way. Both have filed an application for exemptions to permit EVFS-trained and equipped crews at trained airlines and air taxis to start a category 1 instrument approach with 33% lower visibility minimums, as in Europe, succeeded by a 100ft decision height.

The move is viewed as a forerunner to what will sooner or later be a amendment of FAA rules that will permit other properly trained and equipped crews to do the similar in the Part 121 and Part 135 sectors.

FedEx is holding a FAA certification of a Honeywell/Elbit HUD and Kollsman infrared sensor combination. This system is being installed in its Boeing MD-10 and MD-11 fleet. NetJets has also business jets which are Gulfstream G450 and G550. These jets have an EFVS consists of Honeywell-built HUDs and Kollsman sensors which previously qualified for the reduced landing minimums under Part 91 rules.

Industry watchers look forward to a approval from the FAA on the applications for exemptions this spring, and also potentially something like a "credit" for lower landing minimums for aircraft and crews that has synthetic vision systems using head-down displays.

In addition to equivalent visual operations (EVO), a joint RTCA and Eurocae panel which has been putting efforts to build up minimum standards for various EFVS and united vision technologies (synthetic vision fused with enhanced vision), in June conceptualize an initial draft of a global policy that would permit the use of EFVS down to the runway.



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