Boeing E-8 JSTARS

• Le moderniser (moteurs, radar, équipements électroniques,...)
  
• Le remplacer par un appareil plus moderne
  
• Le remplacer par des drones (Multi-Platform Radar Technology Insertion Program)
  

USAF Eyes JSTARS Options

The U.S. Air Force this week confirmed that is looking at various options to continue the critical ground surveillance mission performed by its four-decade-old E-8 Joint Surveillance Targeting Attack Radar System (JSTARS) jets.

Acknowledging the critical role the aging planes play in monitoring wide swaths of insurgent territory, the Air Force has kicked off two interrelated efforts aimed at finding the best way to "continue supporting the JSTARS mission," reads a Dec. 8 e-mail from Air Combat Command (ACC) officials.

ACC will start looking at "a wide variety of possible approaches to the JSTARS mission area for the future" when it begins work on an analysis of alternatives in March 2010. The analysis is expected to be complete by mid-2011.
The ACC study will look at everything from upgrading the E-8s to replacing the fleet with a new aircraft and radars including the multiplatform radar insertion program known as MP-RTIP. The powerful active electronically scanned array was originally developed by Northrop Grumman and Raytheon for use on the now-canceled E-10 surveillance plane. A smaller version of that radar is now being put on the Block-40 version of the RQ-9 Global Hawk.
Meanwhile, Air Force Materiel Command's Electronic Systems Center is looking at what it will take to sustain the jets in their current state as well as the options for installing numerous upgrades to the 17-plane fleet, according to the e-mail.
Designed in the late 1980s to spot Soviet tank columns in Europe, the E-8's powerful radars are now being used to spot individual insurgents in Iraq and Afghanistan. The planes have led to the discovery of hundreds of improvised explosive devices, Sen. Saxby Chambliss, R-Ga., said Oct. 1.
However, the hot climate of the Middle East is making it increasingly costly to operate the 707-based jets, which are powered by early-1960s Pratt & Whitney JT3D engines. The planes burn so much fuel in a hot climate that they must immediately refuel from a waiting tanker after taking off from bases in the Middle East.
While Congress and the Pentagon's top weapons buyer, Ashton Carter, want the Air Force to purchase new engines for the JSTARS fleet, the air service has cut procurement money for the effort.
"You need to ask, if they don't want to re-engine the JSTARS, what do they have to replace it with," Lexington Institute analyst Loren Thompson said.
While the service has no immediate plans to replace the plane, the Air Force acknowledges that the E-8 "continues to present challenges in the realm of sustainment and modernization," and this AoA is a step toward addressing those challenges.

E-8C Joint STARS Awarded $223.6 Million Production Contract for New Engines

MELBOURNE, Fla., March 2, 2010 (GLOBE NEWSWIRE) -- The U.S. Air Force awarded Northrop Grumman Corporation a $223.6 million contract for two E-8C Joint Surveillance Target Attack Radar System (Joint STARS) Propulsion Pod System (PPS) shipsets and FAA certification.
Each shipset contains four Pratt and Whitney JT8D-219 engines, pylon assemblies and associated aircraft system interconnections. Deliveries are expected to start in 2011 pending the final military certifications of the engines on "T-3," the Joint STARS test bed aircraft.
"This critical award moves us a step closer to re-engining the Joint STARS fleet," said Tom Vice, sector vice president of the company's Battle Management and Engagement Systems Division. "We've initially demonstrated the JT8D's approximately 21,000 pounds of maximum thrust on T-3 and the performance improvement seen in flight testing is immediately noticeable."
‪The increased power and fuel economy from the new engines – which are widely used in commercial airline fleets – enables the E-8 to fly higher and maintain longer time on station, providing a better view of the battlespace. "With JT8D engines, Joint STARS will be able to take off from shorter runways, increasing basing options and reducing the transit time to get on station," said Vice. "Shorter transit time, along with the improved fuel efficiency and increased reliability of these new engines all translate to more Joint STARS time on station – a critical benefit to U.S. and coalition forces.
"The JT8D's reliability, as demonstrated in commercial service, also addresses the fleet's number one maintenance issue – engines," said Vice. "A business case analysis has shown that this engine upgrade may potentially pay for itself in less than 10 years in the operations, maintenance and fuel savings realized from not having to deal with the old engines."
The Administration's fiscal 2011 budget, currently under consideration by Congressional committees, includes procurement funding for additional shipsets of engines.

Re-engining the E-8 JSTARS

The USA’s E-8 JSTARS is a Boeing 707-300 derivative that provides a picture of the ground situation analogous to the E-3 AWACS’ picture of the air situation. JSTARS aircraft use their radars to determine the direction, speed and patterns of military activity of ground vehicles, helicopters, and even groups of people. They then send this information via secure data links with air force command posts, army mobile ground stations and centers of military analysis around the world. These surveillance and communications relay capabilities are somewhat unique, and have proven extremely useful in a series of conflicts from Desert Storm in 1991 to the present day. Europe originally intended to field a similar, smaller AGS aircraft based on the Airbus A321, but that project has now been cut to a small fleet of RQ-4 Global Hawk UAVs. With the Global Hawk limited by its payload capacity, and the USA’s E-10A program canceled, the USA’s 17-aircraft JSTARS fleet is likely to remain very popular for some time to come.
The question is how to keep that fleet relevant, flying, and allocated among all of the units clamoring for their attention. A range of upgrades were ordered in 2005, and a recent study claims that the structural improvements and other modifications could allow the aircraft to fly safely for another 40-50 years. The number one issue with the JSTARS fleet, however, remains its old JT3D-3B engines, whose core design was first introduced in the 1950s. An upgrade program is underway to address that, and the US Air Force finally appears to be on board.

The Engines

The choice facing the US Air Force involved 2 candidates:

One was GE’s very popular CFM56 high bypass tubofan, which flies on a wide variety of commercial jets including the entire Airbus 320 family, the A340, and Boeing’s 737-300+) and has been used to re-engine the USA’s 707-derived KC-135 Stratotanker fleet. The new KC-135Rs have demonstrated about a 27% fuel savings since the switch, in addition to lower maintenance costs, compatibility with the KC-135 fleet, and the ability to leverage a wider commercial skills base.
The other option would be Pratt & Whitney’s JT8D-219, based on an engine design that was introduced in the mid-1960s. It powers DC-9, MD-80, Boeing 727, and early-model 737 aircraft. While the fuel savings would be slightly smaller, the JT8 has an advantage of its own: no significant aircraft modifications are required, because the engine has the same weight and center of gravity as the older JT3D engines in current use. This seemingly minor feature offers significant capital and time savings for the re-engining program.
In an environment characterized by high availability needs and a cash crunch for investment, the Pratt & Whitney offering won. The JSTARS engine upgrade program is based on the Propulsion Pod System, incorporating Pratt & Whitney’s JT8D-219 jet engine and Seven Q Seven’s pylons, thrust reversers, and instrumentation.
Benefits are expected to include 17% fuel savings, added power generation for future upgrades to the radar sensor and mission equipment, elimination of engine overheating in warm months that sometimes forced the planes to fly at night, and the ability to use shorter runways. That last capability may allow the E-8Cs to fly from runways closer to some of their operating areas, which reduces the need for aerial tankers and adds fuel savings of its own.

Program: Current State

In the wake of the Lexington Institute report listed below, a program update was sought from multiple sources.
Northrop Grumman representatives said that civil certification was completed in October 2008, as noted below. The testbed plane has been flying, and flight tests for military certification remain on track.
Funding for the re-engining program has been appropriated by Congress, and on Sept 30/09 Pentagon technology chief Ashton Carter directed the US Air Force to free up funds for initial production.
The funding is being used to buy JT8D-219 engines and Seven Q Seven’s propulsion pod systems as long-lead material items, which take time to produce. Once military certification was complete, having the equipment on hand would mean that re-engining could begin immediately during the 17-plane E-8C fleet’s routine depot maintenance (PDM) cycles. Each E-8C enters PDM every 18 months, and the inspection and maintenance process last for about 4-6 weeks per plane. The entire E-8C fleet could be re-engined in about 2 years, while remaining available for use at their normal rates.
Beyond the re-engining program, the E-10’s demise may yet see the work on that plane’s full size MP-RTIP radar transferred to the E-8 fleet. Smaller MP-RTIP radars currently fly on RQ-4B Global Hawk UAVs, but a move to install the full version on the E-8 fleet would improve their ability to find ground targets by a factor of 5x-10x.

Poncho (Admin) a écrit:C'est donc un 707-320B Advanced ?
Sacrées nacelles !

Poncho (Admin) a écrit:Merci, c'était l'autre solution...

Le carénages de pylones internes constitue vraiment une signature

Paul a écrit:Il ressemble à Depardieu

c.foussa a écrit:

Poncho (Admin) a écrit:Merci, c'était l'autre solution...

Le carénages de pylones internes constitue vraiment une signature

Il y aussi ce carénage sur le moteur extérieur droit (moteur4); c'est l'emplacement des 3 turbocompresseurs (T/C) qui aident à la pressurisation

Poncho (Admin) a écrit:

Paul a écrit:Il ressemble à Depardieu

Non lui manque le gros bide (bien mis en valeur par une tenue vestimentaire empruntée au clochard du coin)
On sent bien que la Russie a perdu des plumes avec le pétrole à 50$

c.foussa a écrit:


Il y aussi ce carénage sur le moteur extérieur droit (moteur4); c'est l'emplacement des 3 turbocompresseurs (T/C) qui aident à la pressurisation

Merci !

Ce sont des entrées d'air additionnelles sur le portour de la nacelle ?