Aviation Week & Space Technology - January 15, 2015

Direct Signal

LOC Antenna Multipath

Signal Received =

Direct + Multipath

Source: Airbus ProSky

“As soon as we can make it a success and everyone is happy,
we can begin to expand elsewhere,” says Bijou, adding that
the U.S. “would be a good target” for the program.
Other key projects include the introduction of an instru-
ment landing system (ILS) analysis tool known as the Exact
Landing Interference Simulation Environment (Elise), which
assesses the impact on the ILS signal transmission caused
by structures around the airport, aircraft waiting for takeof,
and those on an approach. Airbus built the 3-D analysis tool
in partnership with France’s civil aeronautics academy. Bijou
says airports must assess the ILS signal when upgrading an
ILS from Category 1 (200 ft. minimums) to Category 2 (100
ft.) and Category 3 (50 ft. or lower), a process many airports
are undertaking to provide for more schedule reliability in
bad weather. Traditional 2-D methods tend to be overly con-
servative, he says, which afects airport construction, hold-
ing positions for nearby aircraft, and in-trail separation for
multiple aircraft on an approach.
Bijou says in-trail spacing on an approach is dictated first
by wake separation constraints and second by the ILS signal-
masking efects of the lead aircraft on those behind it on
the approach. If wind conditions allow for closer separation,
masking can become the primary constraint, leading to re-
duced separation with the Elise analysis. Bijou says testing
has shown that in-trail separation can be reduced by 2 nm for
some aircraft pairs compared to the existing constraints for
ILS masking. “This is massive,” he says. Airbus ProSky will
test an “optimized operation” concept of reduced ILS spacing
behind medium-sized aircraft in low visibility conditions in
Zurich, followed by tests at London Heathrow and Peking.
Heathrow is already using an optimized approach with its mi-
crowave landing system, but not for the more common ILS.
Monte Belger, president of Metron, says the FAA is consid-
ering many of the concepts that Airbus ProSky is promoting
in Europe, but under diferent names and formats. He says
the FAA may not be “as far along as Europe” in the imple-
mentation of the projects due to the current high-priority
focus on PBN, multiple runway operations, data communica-
tions and surface movement optimization.
Boeing’s ATM operation, run by the company’s flight ser-
vices division, is immersed in similar consultation projects

for PBN and advanced ATM both in the U.S. and abroad,

including a dynamic tailored arrival project at Amsterdam

Schiphol Airport within the next year. At the same time,

it promotes subscription services to airlines for efciency

tools under its InFlight Optimization brand, including direct

routes and wind updates. “We have research projects that

couple-in things Boeing has already transitioned into use,”

says Jere “Chip” Meserole, director of Advanced Air Trafc

Management for Boeing. “We bring the next level of improve-

ment to it.”

The impending Schiphol trial, in cooperation with Dutch

air navigation services provider, LVNL, involves developing

a trajectory predictor and automation on the ground that

can be sent via data link to an aircraft for a dynamic tailored

arrival. The system will consider all the required arrival pro-

cedures, up-to-date winds and other trafc constraints to

create a path and speed schedule that optimizes the descent

path to a merge point for each flight. The information will

be sent to the pilot in cruise flight before top-of-descent. A

button-push for confirmation will automatically enter the

path into the flight management system (FMS).

Another research project, with the Dutch meteorological

agency, will investigate the holistic benefit of receiving wind

updates from one aircraft for the benefit of those behind

it, particularly on a descent. Researchers are considering

several methods for obtaining the data, including down-

linked wind computations from the aircraft’s FMS, ADS-B

or ADS-C avionics, and how each afects a forecast model

that can then be sent up to other aircraft in the form of wind

updates to the FMS.

For its subscription products, Boeing says it now has sev-

eral unnamed U.S. airline customers for its Direct Route ser-

vice, which helps airlines identify segments of a route where

pilots can bypass a waypoint to cut track miles, fuel burn

and flight time. Boeing originally licensed the software from

NASA’s Ames Research Center and incorporated it into an

application. The tool runs continuously in the background,

68 AVIATION WEEK & SPACE TECHNOLOGY/JANUARY 15-FEBRUARY 1, 2015 AviationWeek.com/awst

AIR TRAFFIC MANAGEMENT

Airbus ProSky uses a 3-D analysis program to better

estimate the efects of structures and aircraft on preci-

sion ILS beams.