Bell 525 Relentless

Last updated

Bell 525 Relentless
525 GKY (31495047476).jpg
Prototype of the Bell 525 in flight
RoleSuper-medium-lift utility helicopter
National originUnited States
Manufacturer Bell Textron
First flight1 July 2015
StatusUnder development
Produced2015–present

The Bell 525 Relentless is an American super-medium-lift helicopter, under development by Bell Textron. The Bell 525 was unveiled at the 2012 Heli-Expo in Dallas, Texas in February 2012. The helicopter first flew on 1 July 2015. It is designed to transport up to 19 passengers. [1] The aircraft is the first fly-by-wire civilian aircraft and suffered a crash of its prototype, and is still slowly working towards certification. As of 2024, Bell is still working towards completing flight certification [2] it has secured its first order.

Contents

It is a twin turbine engine helicopter with a composite and metal airframe that is in the latter stages of its development.

Development

Bell announced its new project after the Bell 429 and Bell V-22, the super medium Bell 525, previously it was known as Project X or Magellan. The Helicopter is overall designed for trips of 50 to 500 nautical miles, and has a 5-blade main rotor powered by twin engines, digital controls and Garmin G5000H screen, with planned seating for 16-20 people. [3] The flight software is intended have features that enable single-pilot operation of the helicopter. [3]

The Bell 525's maiden flight was planned for late 2014. [4] PHI, Inc. was the launch customer for the type, [5] but as of 2016 is no longer the launch customer. [6] After a six-month delay, the Bell 525 prototype first flew in July 2015. At that time, Bell predicted certification to be completed by the end of 2017. [7] [8] The FAA suggested special rules in May 2016, to address the fly-by-wire concept. [9]

July 2016 crash

At approximately 11:48 AM Central Daylight Time on July 6, 2016, the prototype crashed during a test flight near Italy, Texas, killing the two occupants. [10] The aircraft, registration N525TA, broke up in flight [11] while traveling about 229 mph (199 kn) at an altitude of about 2,000 feet (610 m). [12] During flight testing of the prototype, a severe vibration in the main rotor lead to sequence of events causing the break up of the aircraft. An oscillation in the main rotors of scissoring type caused a 6 hertz vibration in the airfame, which lead to a bio-mechanical feedback loop transmitted from the pilot seat to the pilot and controls among other issues. The accident happened during simulated one engine out test, that used special software to lower the output of both engines. There are many other aspects to conditions that lead to the accident. [13]

The crash delayed the expected certification [12] beyond 2017. [14] In February 2018, Bell predicted certification to be completed by late 2018 or early 2019. [1] In December 2018, 1,300 hours of turn time and 900 hr of flight were accumulated, towards a 2019 US type certification. In early 2019, two helicopters were to be tested in cold weather in Yellowknife, Northwest Territories, Canada, as a third prototype was to validate performance in snowy north continental US. [15]

Bell has worked with the FAA to work towards certifying the new design, and examples of tests include running simulated icing conditions. [16]

Intended market

The helicopter is the largest civilian helicopter made yet by Bell, and can carry 16 passengers and two crew. [17]

Bell has also pitched the Bell 525 to military customers as a 20-passenger utility and troop transport or search and rescue (SAR) aircraft. [18] Bell sought to sell the 525 to the United Kingdom for its New Medium Helicopter program, which aims to replace the RAF's Puma (SA330) helicopters, [19] but Bell's proposal did not make it past the pre-qualification questionnaire stage for the UK's medium lift programme. [20]

In 2019 Bell displayed the Bell 525 at the Paris Air Show, updating the market on its progress and demonstrating some of the aircraft systems. [21]

In 2024, Bell announced its first customer for the Bell 525, an order for ten to operate in the North Seas offshore market by the Norwegian oil company Equinor to be delivered in the late 2020s. The customer noted its thirty year relationship with Bell and its products. [17]

Design

Bell 525 on display at the Paris Air Show of 2019 Paris Air Show 2019, Le Bourget (SIAE1134).jpg
Bell 525 on display at the Paris Air Show of 2019

The Bell 525 is designed to meet a requirement for a medium-lift helicopter. It will be constructed primarily from composites and metal and is to be the first commercial helicopter to incorporate fly-by-wire flight controls, [22] with tactile cues. The system is triple redundant, and is developed in two simulator environments. [23] The 525 is powered by a pair of GE CT7-2F1 turboshaft engines, with a new composite five-blade main rotor system. [5] The cost of the 525 has not yet been determined, but it is expected to be cost competitive on missions between 50 and 400 nmi, performed by helicopters such as the AgustaWestland AW139 and Sikorsky S-92. [24] [25]

The Bell 525 is designed to fit the emerging "Super-Medium" size category suited ideally to support offshore oil and gas operations. [26] Half of the customers come from that sector. [23] Helicopters under development in the same class are the Airbus Helicopters H175 and the AgustaWestland AW189. [5] The 525 is to be certified in Category A Takeoff class, at maximum gross weight. This involves being able to continue a takeoff (or landing) after one of the helicopter's two turbine engines fails at any point. It should be capable of carrying 19 passengers, more than any existing super-medium helicopter. [1] It is designed for two pilots with 16 passengers in the standard configuration and two pilots with 20 passengers in high-density seating. [27]

Specifications (Bell 525)

Data from "Bell 525", [28] Flight Global [29]

General characteristics

Performance

Avionics

See also

Related development

Aircraft of comparable role, configuration, and era

Related Research Articles

<span class="mw-page-title-main">Tiltrotor</span> Aircraft type

A tiltrotor is an aircraft that generates lift and propulsion by way of one or more powered rotors mounted on rotating shafts or nacelles usually at the ends of a fixed wing. Almost all tiltrotors use a transverse rotor design, with a few exceptions that use other multirotor layouts.

<span class="mw-page-title-main">Leonardo AW609</span> Twin-engine tiltrotor VTOL aircraft

The Leonardo AW609, formerly the AgustaWestland AW609, and originally the Bell-Agusta BA609, is a twin-engined tiltrotor VTOL aircraft with an overall configuration similar to that of the Bell Boeing V-22 Osprey. It is capable of landing vertically like a helicopter while having a range and speed in excess of conventional rotorcraft. The AW609 is aimed at the civil aviation market, in particular VIP customers and offshore oil and gas operators. It has progressed from a concept in the late 1990s, to development and testing, and is working towards certification in the 2020s.

<span class="mw-page-title-main">Bell 206</span> Utility helicopter family by Bell

The Bell 206 is a family of two-bladed, single- and twin-engined helicopters, manufactured by Bell Helicopter at its Mirabel, Quebec, plant. Originally developed as the Bell YOH-4 for the United States Army's Light Observation Helicopter program, it was not selected by the Army. Bell redesigned the airframe and successfully marketed the aircraft commercially as the five-place Bell 206A JetRanger. The new design was eventually selected by the Army as the OH-58 Kiowa.

<span class="mw-page-title-main">PZL SW-4 Puszczyk</span> Polish light utility helicopter

The PZL SW-4 Puszczyk is a Polish light single-engine multipurpose helicopter manufactured by PZL-Świdnik. Following a protracted development, the SW-4 entered service in 2002, the primary operator of the type has been the Polish Armed Forces. The SW-4 was further developed by PZL-Świdnik and corporate parent AgustaWestland into an optionally piloted vehicle, the SW-4 Solo. From 2016 onwards, the type has been marketed to civil operators as the AW009, while the SW-4 designation is used for the military market.

<span class="mw-page-title-main">Bell 407</span> Civil 7-seat utility helicopter

The Bell 407 is a four-blade, single-engine, civil utility helicopter. A derivative of the Bell 206L-4 LongRanger, the 407 uses the four-blade, soft-in-plane design rotor with composite hub developed for the United States Army's OH-58D Kiowa Warrior instead of the two-blade, semi-rigid, teetering rotor of the 206L-4.

<span class="mw-page-title-main">Kamov Ka-60</span> Utility helicopter

The Kamov Ka-60 Kasatka (Russian: "Касатка", is a Russian medium twin-turbine military transport helicopter under development by Kamov. It performed its first flight on 24 December 1998.

<span class="mw-page-title-main">Sikorsky S-92</span> Transport helicopter family by Sikorsky

The Sikorsky S-92 is an American twin-engine medium-lift helicopter built by Sikorsky Aircraft for the civil and military helicopter markets. The S-92 was developed from the Sikorsky S-70 helicopter and has similar parts such as flight control and rotor systems.

<span class="mw-page-title-main">AgustaWestland AW139</span> Twin-engined, medium-lift helicopter manufactured by Leonardo

The AgustaWestland AW139, now known as the Leonardo AW139, is a 15-seat medium-sized twin-engined helicopter developed and produced by the Italian helicopter manufacturer AgustaWestland, now part of Leonardo. It is marketed at several different roles, including VIP/corporate transport, military use, offshore transport, firefighting, law enforcement, search and rescue, emergency medical service, disaster relief, and maritime patrol.

<span class="mw-page-title-main">Eurocopter EC130</span> Single-engine light helicopter

The Airbus Helicopters H130 is a single engine light utility helicopter developed from the earlier Eurocopter AS350 Écureuil, one of the primary changes from which was the adoption of a Fenestron anti-torque device in place of a conventional tail rotor. It was launched and produced by the Eurocopter Group, which would later be rebranded as Airbus Helicopters.

<span class="mw-page-title-main">AgustaWestland AW119 Koala</span> Single-engine, eight-seat utility helicopter manufactured by Leonardo

The AgustaWestland AW119 Koala, produced by Leonardo since 2016, is an eight-seat utility helicopter powered by a single turboshaft engine produced for the civil market. Introduced as the Agusta A119 Koala prior to the Agusta-Westland merger, it is targeted at operators favoring lower running costs of a single-engine aircraft over the redundancy of a twin.

<span class="mw-page-title-main">Bell 214ST</span> Type of aircraft

The Bell 214ST is a medium-lift, twin-engine helicopter descended from Bell Helicopter's ubiquitous UH-1 Huey series. Though it shares a type number with the somewhat-related Bell 214, the 214ST is larger and of quite different appearance.

<span class="mw-page-title-main">Eurocopter EC225 Super Puma</span> Type of aircraft

The Airbus Helicopters H225 is a long-range passenger transport helicopter developed by Eurocopter as the next generation of the civilian Super Puma family. It is a twin-engined aircraft and can carry up to 24 passengers along with two crew and a cabin attendant, dependent on customer configuration. The helicopter is marketed for offshore support and VIP passenger transport duties, as well as public service missions.

<span class="mw-page-title-main">Airbus Helicopters H175</span> Medium utility helicopter

The Airbus Helicopters H175 is a 7-ton class super-medium utility helicopter produced by Airbus Helicopters. In China, the H175 is produced by the Aviation Industry Corporation of China (AVIC) as the Avicopter AC352. Originally launched as the Eurocopter EC175 and the Harbin Z-15, it has been referred to as being a 'super-medium' helicopter.

<span class="mw-page-title-main">Sikorsky S-97 Raider</span> American high-speed scout and attack compound helicopter

The Sikorsky S-97 Raider is a high-speed scout and attack compound helicopter based on the Advancing Blade Concept (ABC) with a coaxial rotor system under development by Sikorsky Aircraft. Sikorsky planned to offer it for the United States Army's Armed Aerial Scout program, along with other possible uses. The S-97 made its maiden flight on 22 May 2015.

<span class="mw-page-title-main">AgustaWestland AW189</span> Twin-engined, medium-lift helicopter manufactured by Leonardo

The AgustaWestland AW189 is a twin-engined, super-medium-lift helicopter manufactured by Leonardo S.p.A. It is derived from the AW149, and shares similarities with the AW139 and AW169.

<span class="mw-page-title-main">AgustaWestland AW169</span> Twin-engine light utility helicopter

The AgustaWestland AW169 is a twin-engine, 10-seat, 4.8t helicopter developed and manufactured by the helicopter division of Leonardo. It was designed to share similarities with the larger AgustaWestland AW139 and AgustaWestland AW189.

<span class="mw-page-title-main">Kopter AW09</span> Swiss light helicopter

The Kopter AW09 is the Leonardo Helicopter Division's five-to-eight seat, single-engine multirole helicopter which is currently under development at Kopter’s facilities. It is a clean-sheet design amongst a market sector dominated by decades-old airframe designs.

<span class="mw-page-title-main">Airbus Helicopters H160</span> Type of aircraft

The Airbus Helicopters H160 is a medium utility helicopter developed by Airbus Helicopters. Formally launched at Heli-Expo in Orlando, Florida on 3 March 2015, it is intended to replace the AS365 and EC155 models in the firm's lineup. In June 2015, the first test flight took place. It received its EASA type certification in July 2020, and first deliveries were in December 2021.

<span class="mw-page-title-main">Leonardo Next-Generation Civil Tiltrotor</span> Twin-engine tiltrotor aircraft demonstrator

The Leonardo Next-Generation Civil Tiltrotor is a tiltrotor aircraft demonstrator designed and developed by the Italian aerospace company Leonardo S.p.A. Studies for a two times larger tiltrotor than the AgustaWestland AW609 started in 2000. Since 2014, its development is sponsored by the European Union's Clean Sky 2 program. By May 2021, major components were under production By 2023, the maiden flight had been pushed back to 2024, from a 2020 initial plan.

<span class="mw-page-title-main">2016 Bell 525 Relentless prototype crash</span>

The 2016 Bell 525 Relentless prototype crash occurred during a test flight on July 6, 2016, near Italy, Texas, destroying the prototype Bell 525 Relentless helicopter and killing the two occupants. The helicopter broke up in flight while traveling about 229 mph (199 kn) at an altitude of about 2,000 feet (610 m); the main rotor contacted and severed the tail boom due to severe vertical oscillations. The crew were performing one engine inoperative (OEI) recovery testing; the test induced a scissors-mode vibration in the main rotor, which resulted in involuntary collective control input. The unintended biomechanical feedback loop exacerbated the vibration, until the rotor contacted the tail-boom.

References

  1. 1 2 3 Osborne, Tony (February 23, 2018). "Bell Pressing Ahead With Fly-By-Wire 525 Certification". Aviation Week Network. Retrieved October 22, 2021.
  2. "Bell aiming to wrap up 525 certification flight tests in first half of 2024". Vertical Mag. Retrieved April 26, 2024.
  3. 1 2 "New Aircraft Preview: Bell 525 Relentless". Business Jet Traveler. January 27, 2015. Retrieved April 26, 2024.
  4. "Bell Helicopter Reveals the Latest in the Bell 525 Program during HELI-EXPO 2014" Archived 2014-04-29 at the Wayback Machine . Bell Helicopter, February 25, 2014. Archive link appears dead.[ dead link ]
  5. 1 2 3 Norris, Guy (February 20, 2012). "Bigger Bell (web title: Bell Rings In Changes With Super-Medium 525 Relentless)". Aviation Week & Space Technology. 174 (7). New York: McGraw-Hill: 36–37.[ permanent dead link ]
  6. Drew, James. "VIDEO: Bell relentlessly pursuing 525 despite market troubles". FlightGlobal. Reed Business Information. Retrieved August 15, 2018.
  7. Perry, Dominic (July 2, 2015). "VIDEO: Successful first flight for new Bell 525 Relentless". Flightglobal.com . Retrieved August 16, 2015.
  8. "Eclipse Special Edition and Bell Model 525 News from The Weekly of Business Aviation". Aviation Week Network. July 7, 2015. Retrieved October 22, 2021.
  9. "Federal Register – Special Conditions: Bell Helicopter Textron, Inc. (BHTI), Model 525 Helicopters; Interaction of Systems and Structures" . Retrieved August 6, 2016.
  10. Ramirez, Domingo (July 6, 2016). "Bell helicopter crashes in Ellis County, two reportedly killed". Fort Worth Star-Telegram . Retrieved July 6, 2016.
  11. "NTSB Identification: DCA16FA199". NTSB . Retrieved August 6, 2016.
  12. 1 2 "NTSB releases preliminary report on Bell Helicopter crash". Fort Worth Star-Telegram . Retrieved August 6, 2016.
  13. Rotorcraft, Mark Huber • Contributor-. "NTSB: Severe Vibration Triggered Bell 525 Breakup | AIN". Aviation International News. Retrieved April 26, 2024.{{cite web}}: |first= has generic name (help)
  14. Grady, Mary (January 16, 2018). "NTSB Cites 'Adverse Feedback Loops' In Bell Crash". AVweb. Retrieved January 17, 2018.
  15. "Bell 525 helicopters head to Canada for cold-weather testing". Flightglobal. December 18, 2018.
  16. Editor, Kerry Lynch •; magazine, AIN monthly. "Bell 525 Certification on Horizon This Year | AIN". Aviation International News. Retrieved April 26, 2024.{{cite web}}: |last= has generic name (help)
  17. 1 2 Editor, Kerry Lynch •; magazine, AIN monthly. "Bell Lands First Purchase Agreement for 525 Super-medium Helicopter | AIN". Aviation International News. Retrieved April 26, 2024.{{cite web}}: |last= has generic name (help)
  18. Perry, Dominic (August 25, 2017). "PICTURES: Bell targets military market with 525 helicopter". Flight Global.
  19. "Bell touts 'ideal' 525 for UK New Medium Helicopter requirement". Janes.com.
  20. Jennings, Gareth (November 2, 2022). "UK downselects New Medium Helicopter contenders". Janes.com. Retrieved December 4, 2022.
  21. "Bell Helicopter will showcase a number of updates and aircraft at Paris show". Helicopter Investor. Retrieved April 26, 2024.
  22. "Bell's 525 is Relentless". Sport Aviation: 14. April 2012.
  23. 1 2 "'Flight Testing' the Bell 525 Relentless". Vertical Mag. June 30, 2016. Retrieved October 22, 2021. Archived on 23 July 2014.
  24. "Bell 525 Brochure" Archived October 5, 2013, at the Wayback Machine . Bell Helicopter, February 2012. pdf
  25. "'Relentless' 525 To Be Largest Bell Helicopter" Archived September 7, 2014, at the Wayback Machine . AINOnline, February 2012.
  26. CFM, In association with; Airshow, In association with Singapore; Recruitment, In association with GOOSE; Trimble, Stephen (February 23, 2015). "ANALYSIS: Oil prices create super uncertainty". Flight Global. Retrieved October 22, 2021.
  27. "Bell 525 Relentless". Bell Flight. Retrieved October 22, 2021.
  28. "BELL 525 RELENTLESS". bellflight.com. Archived from the original on July 11, 2019.
  29. CFM, In association with; Airshow, In association with Singapore; Recruitment, In association with GOOSE; Perry, Dominic (September 21, 2015). "Bell confident on further 525 performance boost". Flight Global. Retrieved October 22, 2021.