Canadian American Strategic Review


Replacing the


 A  Modest

In Detail

DND 101

Background  —  Aurora Alternatives  —  Global Express / R1 Sentinel

Update: In Sept 2013, Raytheon pitched a Sentinel R1 software change which would allow the RAF to shift roles from ground- to maritime surveillance filling a current capability gap.  In its maritime surveillance role,  the Sentinel wouldn't be armed or have any ASW capability.

An aircraft  under  serious consideration as an  Aurora alternative is Bombardier's Global Express bizjet. This interest will  have  been sparked,  in part, by  entry into RAF service of five battlefield surveillance derivatives, the R1 Sentinel. This is considered a Raytheon system but  Bombardier  remains responsible for producing the actual airframe  –  final assembly is at Downsview, ON.

The R1 Sentinel's main external changes are obvious: a large satellite link radome on the upper fuselage and the 4.6m-long pannier beneath the main cabin holding the radar antenna. A pair of  auxiliary fins and small fairings were added  to restore stability. This is an interesting adaptation and comparatively inexpensive by the standards of  such specialized aircraft. [2] However, the R1 Sentinel is dedicated to its surveillance role and is in no way a CP-140 Aurora-like maritime patrol aircraft.

But Air Force planners may not  be looking for a direct replacement for the Auroras. Reportedly, the favoured plan is to fit the sensors and mission systems controls from the cancelled  Aurora modernization to the newer Global Express airframes.  In engineering terms, this is easier than it sounds. The new sensors and computers were integrated as part of AIMP  Block III. This would be repeating the Aurora model of  putting already-integrated systems into a proven airframe. [3]

Of course, in reality, integrating any system into a new "platform" is never simple. Nor is adapting airframes designed for one type of mission  (high altitude cruising, in this case) for another (low altitude maritime patrol ). If the Global Express is chosen, these Aurora replacements will fly very different missions from the CP-140s. They'd  transit much more quickly, fly higher, and likely be unarmed.[3]

  Raytheon R1 Sentinel / Bombardier Global Express  –  Specs
  Dimensions:   span: 28.6m, length: 30.3m, height: 7.57m
  Powerplant:   2 x 65.5kN (14,750 lbst) RR BR710 turbofans
  max speed: 950 km/h,  max cruise: 904 km/h,
  operating altitude: 15,000m (50,000 feet)
  Weights:   empty weight: 22,817kg, MTOW: 43,094kg
  Maximum range:   12,000km  (6500 nm), endurance: 14+ hours
  Crew:   2 x flightcrew, 3 mission systems operators

[1] Test aircraft C-FBGX was the original prototype Global Express. Bombardier converted C-FBGX to act as the R1 Sentinel development prototype. Actual systems integration was done at Raytheon's Greenville, Texas facility but this would not be relevant to a patrol aircraft.
[2] Affordability is relative. Reportedly, Britain paid just over 1B (or Cdn $1.41B) for five aircraft and their vehicle-based ground stations. By comparison, unit cost for a single US E-8C JSTARS aircraft (without GCS) is listed at US $244.4M (US $308M in adjusted 2007 dollars).
[3] The suitability of this would depend upon the new mission profile. If emphasis were on higher altitude surveillance missions, this may work just fine. Maritime patrol demands slower flying at low altitude which would greatly shorten the range of a Global Express/ Sentinel. A modest armament would be possible – on wing pylons or in a small bomb bay within a ventral gondola. Neither are small modifications.