The Boeing 737-900 is a civilian, passenger, regional and medium-haul aircraft that is part of the 737-X or NG models (Next Generation), which was launched in 1993.
The 737NG series includes the 737-600, -700, -800, and -900 series, significantly different from the first aircraft of the 737 families. This is a completely new series, which has little in common, except for the fuselage design, with the original Boeing 737 aircraft. The biggest changes were the new wings, new avionics, advanced engines. On NG, the so-called “glass cockpit” – equipped with displays on cathode ray tubes, and later on liquid crystals) instead of the usual “alarms” – analog devices, and digital systems. Most of these systems were borrowed from the Boeing 777, as well as the design of the cockpit and passenger compartment. The total number of aircraft parts was reduced by a third, which reduced its weight and improved handling. Additional transformations also include optional vertical wingtips – “Winglets”, which significantly reduce fuel consumption and improve takeoff and landing performance. It became possible to install “winglets” on airplanes that were not originally equipped with them, including earlier types.
The 737-900 airliner is similar to the 737-800 but has an elongated 2.8 meters fuselage. The avionics complex is similar to that used on 777 series aircraft with six color TFT displays. It accommodates passengers more than the Boeing 707 and acts in the same class as the Boeing 757. In one week, orders for -900 were received more than for the entire 757 families for the entire 2004. In 2005, the Boeing 737 lost one of its main distinguishing features – these are additional “brow” windows located on top of the main windshield in the cockpit. In the 60s, such glasses were a requirement of the US Federal Aviation Administration for flight certification to improve visibility at large roll angles. However, this is not required today, and Boeing offers aircraft customers the option of choice.
For a more successful competition with Airbuses, the Boeing 737-900 model was developed – the longest aircraft in the family, but noticeably smaller than an airbus. The number of doors was not increased, as required by the Federal Aviation Administration. Therefore, the passenger capacity of the aircraft was significantly reduced not so much due to design flaws, but because of laws.
The first flight took place on August 3, 2000, and the first plane was delivered to Alaska Airlines on May 15, 2001.
Air conditioning / pneumatic system: The Boeing 737-900 is a long aircraft that has two cabin temperature zones. The power supply system was slightly changed compared to the 737 Classic: the power distribution system was changed, a rechargeable battery was added to start the APU and new generators were installed, combined with a 90 KVA Integrated Driven Generator (IDG) constant-speed drive. On the electric control panel, a digital indicator is installed instead of arrow pointers.
In the flight control system, new double-slotted flaps were used, one section of slats and spoilers was added (due to the extension of the wing by 5.5 meters).
Fuel system – the capacity of the tanks has been increased to 20800 kg, the fuel tanks have been changed: the central tank occupies not only the center section but also a part of the wing from the root to the engine pylon. The arrangement of the pumps also changed and a system for removing water from the tanks was added. The hydraulic system of the 737 Classic and Boeing 737-900 is very different from the 737 Original. Energy consumers are redistributed in it, and one engine and one electric hydraulic pump are operated for each of the main systems.
The landing gears are redesigned, higher than the 737 Classic, and also reinforced depending on take-off weight. Since 2008, it has become possible to install new carbon brakes with less weight and longer life.
The main difference between the architectural avionics complex of the aircraft is the use of the Honeywell Common Display System (CDS) display complex developed by the Boeing 777 aircraft. The CDS includes two Display Electronic Unit (DEU) computers, six Display Unit (DU) LCD indicators, two panels control, and switching equipment. The indication can be transferred from one display to another. In addition to the main purpose – the creation of an indication, CDS is a central interface system. CDS can also be supplemented with a collimator indicator (indicator on the windshield) – Head-Up Display (HUD).
Another difference is the integration of the inertial navigation system and the air signal system into one system – Air Data and Inertial Reference System (ADIRS), which consists of two Air Data and Inertial Reference Unit (ADIRU) units. The aircraft is certified for landing in the conditions of the ICAO CAT IIIB meteorological minimum.
As a power plant, CFM56-7B series turbofan engines manufactured by CFM International are used. This engine has more power than the CFM56-3. One of the fundamental differences between the Boeing 737-900 and Classic is the use of fly-by-wire engine remote control. All control is provided by the Engine Control Computer (EEC), acting on the hydromechanical unit (HMU). The system used is similar to the FADEC system used on an Airbus A320 aircraft. The difference between the Boeing 737-900 and the Airbus lies in the application of the concept of active engine control levers (ORE): the traction machine does not act directly on the EEC, but on the ORE, so the position of the ORE corresponds to the specified engine thrust.
After the production of the 757th was completed in July 2005, Boeing announced the start of work on the creation of the 737-900ER (Extended Range) option, previously known as the 737-900X. Model 737-900ER is the same in size as the 737-900, equipped with additional tanks and a pair of doors. Passenger capacity has been increased to 215 people, which is 26 more than 737-900. The first aircraft is planned to be delivered in the first half of 2007. The advanced wing design provides low fuel consumption at a cruising speed of 0.78 Mach. The first customers were Alaska Airlines (737-900) and Lion Air (737-900ER) with an order for 30 aircraft.
Based on the aircraft, the BBJ3 variant has also been developed.
Work on the 737-700ER was also announced. In terms of size, it is again similar to its prototype, but additional fuel tanks are installed on it and the maximum take-off weight is increased. The first customer is the Japanese All Nippon Airways.
- Modification: Boeing 737-900
- Wingspan, m: 34.30
- Length of aircraft, m: 42.10
- The height of the aircraft, m: 12.55
- Wing Area, m2: 124.60
- Weight kg: empty loaded aircraft 42490; maximum take-off 79,000
- Engine type: 2 turbofan engines CFM International CFM56-7V
- Thrust, kgf: 2 x 12394
- Maximum speed, km / h: 970
- Cruising speed, km / h: 925
- Practical range, km: 5084
- Practical ceiling, m: 12500
- Crew: 2
- Payload: of 177 passengers in a cabin of two classes or the tourist class 189 people.