Calm and Comfortable

Tauhid Nur Azhar

Photo by Gary Lopater on Unsplash

Today, at the end of a weekend in late December, I am at the departure area of Terminal 3 at Soekarno-Hatta Airport. After the inspection process at the departure gate right in front of the boarding bridge, I enter the spacious waiting room and look for a place to sit between gates 17 and 23. The boarding gate for my Garuda Indonesia flight is located at one of the gates in this area. Of course, since the boarding and takeoff schedule is still quite a while away, there is still time for me to perform the Subuh prayer first and enjoy a cup of hot cappuccino in the business lounge, which I can access for free with my bank’s priority card. When will the next free all-you-can-eat breakfast be?

The boarding time seems to arrive without me realizing it. By showing my ID card (KTP) and the QR/barcode on the e-boarding pass on my phone screen, I am granted access to walk down the jet bridge and enter the fuselage or cabin of the Boeing 737–800 NG aircraft of Indonesia’s national airline, Garuda Indonesia. At that time, Garuda Indonesia was still part of one of my WA groups, APIC Mobility, led by Kang Irvan, who was adept at solving various company management issues that arose.

Just like the song by Pak Kusir that I often sang when I was in kindergarten at TK Nasional Madiun, led by the legendary headmaster, Bu Tien, “sitting in front,” as Pak Kusir would say, right behind Pak Pilot, separated only by the lavatory, pantry, and Mbak Pramugari’s seat, or looking at her uniform, she seemed to be a flight attendant.

While enjoying the spacious, comfortable seat and the soft leather upholstery, as well as covering my face with a small, warm, wet towel offered by the flight attendant, I take a deep, satisfying breath. This aircraft is truly comfortable. But this comfort is short-lived because soon after takeoff and as the aircraft climbs, I start to feel the jolts and shakes as the aircraft passes through thick, dark clouds visible from the window, resembling cotton candy.

Several times, I even see lightning flashing in the distance. Instantly, my heart races, and I pray for our safety.

Although logically, I know for sure that this Boeing 737–800 NG aircraft from Garuda that I am boarding is equipped with various technologies that ensure flight safety, environmental friendliness, fuel efficiency, and comfort, as a mere human facing the vastness and grandeur of nature, I feel helpless.

The Boeing 737–800 NG (Next Generation) that I am boarding is not just any ordinary passenger aircraft. This aircraft has undergone significant design improvements, equipped with advanced avionics systems and fuel-efficient CFM engines, making it one of the most advanced and successful series in the Boeing lineup.

The dimensions of this aircraft are compact but not cramped. Its length is 39.5 meters, with a height of 12.5 meters and a wingspan of 35.8 meters. Imagine lining up three TransJakarta buses; that’s roughly the wingspan of the 737–800 NG. The aircraft’s body has a diameter of 3.76 meters, proportionally enough to accommodate up to 189 passengers in a single-class configuration.

However, what is even more impressive is the wing area, which reaches 124.6 square meters. Known as the “giant sail,” these wings are a medium for innovations such as winglets and split scimitar winglets. Winglets are like thin, sharp blades that cut through the air to reduce high-pressure air vortices.

In aerodynamic terms, they increase the lift-to-drag ratio, making the aircraft more fuel-efficient. Moreover, with the split scimitar winglet option, the wings are equipped with a “double fin”; one curving upwards, the other downwards, each with a curved tip known as the scimitar tip.

This technology can reduce fuel consumption by approximately 2.2% compared to conventional winglets. If scaled annually, a single aircraft can reduce CO2 emissions by more than 510 tons per year, equivalent to saving thousands of trees in the tropical forests of Kalimantan and Sulawesi, which I am currently visiting.

From my leather-upholstered seat, the engine noise from the wing behind sounds like the bass rumble of a Metallica concert. It roars and rumbles during takeoff but smoothens out as it reaches cruising altitude, which is currently at 36,000 feet, or commonly known in aviation terms as FL360, or flight level 36,000 feet.

I imagine the engine, the CFM56–7B, which can typically generate a thrust of approximately 121.4 kilonewtons (equivalent to 27,300 pounds of force) per engine. Like a monster with hundreds of horsepower, but wrapped in sophistication and high-level efficiency. Not only powerful, this engine is also equipped with support technologies to reduce operational costs for the airline.

The CFM56–7BE “Evolution” series, for example, increases fuel efficiency by around 1–2% per year and optimizes carbon dioxide emissions more effectively. Ultimately, this innovation allows airlines to maintain competitive ticket prices without sacrificing profit margins.

After the initial jolts and shakes shortly after takeoff, the flight attendant announces that all passengers should keep their seatbelts fastened and refrain from leaving their seats due to bad weather conditions. There might be a storm above the Java Sea where I am, while feeling the increasingly chilly air.

Outside the window, lightning flashes several times from the distance, reflecting off the wing’s surface. But to calm myself, I try to find a comedy movie on the AVOD (audio video on demand) system, a personal entertainment service provided by this full-service airline. However, due to the severe turbulence, I cannot fully enjoy the movie. To calm myself further, I try to recall various information I have read and studied about how this Boeing 737–800 NG is equipped with an advanced radar (concept) called E-Turb (Enhanced Turbulence) Radar. Known as the “third eye,” this radar can detect atmospheric conditions up to 25 nautical miles ahead, identifying areas of air turbulence or ice crystals that indicate turbulence.

Imagine it as a Doppler sensor that can read the direction and speed of particles in the air, where the radar then processes this data into warnings on the cockpit screen. Magenta indicates a serious threat, and it seems that this warning is currently being displayed in the cockpit.

Based on the technology developed from the research by Buck and Bowles, 2009, titled “A Methodology for Determining Statistical Performance Compliance for Airborne Doppler Radar with Forward-Looking Turbulence Detection Capability,” pilots can make quick decisions, such as increasing or decreasing the flight altitude to avoid turbulent air pockets.

Moreover, it is a fact that the Boeing 737–800 NG series is equipped with features such as the Vertical Situation Display (VSD), Head-Up Display (HUD), and TCAS (Traffic Collision Avoidance System), which are like “super gadgets” in a science fiction novel. All are designed to ensure that pilots always have situational awareness.

It cannot be denied that modern aircraft pilots, including those of the Boeing 737–800 NG, are equipped with various technologies that can minimize human error, one of the main causes of aviation incidents, which often, especially in December, have high incident and accident rates year after year.

Currently, the aviation world is still mourning the accident involving the Boeing 737–800 NG aircraft of Jeju Air at Muan Airport. And the pain has not yet subsided from our realization that on December 28, 2014, there was also the tragedy of Airbus A320 flight QZ8501 of Air Asia crashing into the Karimata Strait.

But with the assurance that the pilots of this flight are highly experienced with thousands of flight hours and rigorous type rating tests, and that this aircraft is highly advanced, with systems and technologies that can anticipate various possibilities based on data received from the weather radar (Wx Radar), EGPWS (Enhanced Ground Proximity Warning System), and FMS (Flight Management System), every maneuver made indicates that the advanced avionics system is working to keep us all safe throughout the flight.

After some time enduring the turbulence, the aircraft finally breaks through the last layer of clouds. The sunlight gently filters through the window, softly illuminating the cabin. The shaking subsides, and the seatbelt sign is turned off. An announcement from the cockpit informs us that the aircraft has reached its cruising altitude, around 36,000 feet, and the rest of today’s flight to the destination airport will proceed in clear weather. Alhamdulillah.

With my breath stabilizing after being slightly erratic earlier, I try to close my eyes. It crosses my mind how small I am in the face of the grandeur of nature. The Boeing 737–800 NG is not just a statistical figure like its cruising speed of 946 km/h or its maximum range of 5,765 km; rather, it is a testament to how humans collaborate with machines and technology to adapt to various dynamics presented by nature.

What we see behind this cabin is the result of the hard work of thousands of engineers, mechanics, and aerodynamics experts over the years. From the design of the wings with thin airfoils to the digital cockpit that feels “user-friendly,” everything functions like pieces of a puzzle that fit together perfectly, implementing substitution seamlessly.

Epilogue

The Boeing 737–800 NG is designed to increase fuel efficiency, reduce noise, and enhance passenger comfort. Therefore, it is no surprise that this aircraft is a mainstay for many airlines around the world for short to medium-haul routes, including Garuda Indonesia.

To get to know this advanced aircraft better, here are some technical data highlights:

Technical Specifications of the Boeing 737–800 Next Generation

Dimensions:

• Length: ±39.5 meters (129 feet 6 inches)
• Height: ±12.5 meters (41 feet)
• Wingspan: ±35.8 meters (117 feet 5 inches)
• Fuselage Diameter: ±3.76 meters (12 feet 4 inches)
• Wing Area: ±124.6 m² (1,341 square feet)

Weight:

• Empty Weight: ±41,413 kg (91,300 lbs)
• Maximum Takeoff Weight (MTOW): ±79,015 kg (174,200 lbs)
• Maximum Landing Weight (MLW): ±65,317 kg (144,000 lbs)

Performance:

• Cruising Speed: ±946 km/h (511 knots, 588 mph)
• Maximum Cruising Speed: Mach 0.82
• Maximum Range: ±5,765 km (±3,115 nautical miles)
• Maximum Altitude: ±12,497 meters (41,000 feet)

Engines:

• Model: 2 × CFM International CFM56–7B
• Thrust: ±121.4 kN (27,300 lbf) per engine

Capacity:

• Passengers: 162 (two-class configuration) to 189 (single-class configuration)
• Fuel: ±26,020 liters (6,873 gallons)

Additional Features:

• Winglets (or the Split Scimitar Winglet option) to increase fuel efficiency
• Digital cockpit with modern avionics
• Wider cabin with larger overhead baggage compartments
• Quieter engines for passenger comfort

One of the keys to the efficiency of the Boeing 737–800 NG lies in its wing design. Compared to its predecessor, the 737–800 NG has a larger wing area and a more advanced airfoil design, which significantly reduces drag (air resistance).

This aircraft is typically equipped with winglets at the wingtips to reduce vortices (air swirls) that often occur at the wingtips. The presence of winglets can save fuel by approximately 6.69% (although real-world efficiency varies between 4.6%–10.5% depending on the route and flight conditions). Airlines can also opt for the Split Scimitar Winglet, which structurally splits into two parts; one extending upwards (upper winglet) and the other downwards (ventral strake). Each is equipped with a curved tip known as the scimitar tip. This unique design can achieve the following:

1. Increase fuel efficiency by approximately 2.2% higher than conventional winglets.
2. Optimize airflow at the wingtips, improving the lift-to-drag ratio.
3. Reduce CO2 emissions by more than 510 tons per aircraft per year.

As a result, fuel consumption per seat can be reduced by 9–14% compared to previous models, while flight duration remains the same.

The Boeing 737–800 NG is powered by two CFM56–7B engines that have undergone various performance enhancements. One significant upgrade is the CFM56–7BE “Evolution,” which can increase fuel efficiency by around 1–2% per year and reduce CO2 emissions. It can also improve the Exhaust Gas Temperature (EGT) margin, making the engine more heat-resistant and durable.

In the long run, this will reduce maintenance costs by up to 4% at maximum thrust ratings. Overall, the CFM56–7B engine can generate thrust ranging from ±24,500–32,900 lbf. Additionally, its fuel consumption is 8% more efficient than the previous CFM56 generation (used in the 737 Classic). The new engine also features a high-pressure turbine airfoil design optimized with 3D design techniques.

The Boeing 737–800 NG is equipped with a suite of advanced avionics features to enhance flight safety, including:

1. Digital Cockpit: LCD screens display flight, navigation, and aircraft system information more clearly and intuitively.
2. Vertical Situation Display: Provides a vertical display of the flight path, helping pilots avoid hazardous areas.
3. Head-Up Display (HUD): Critical information is displayed on the cockpit windshield, allowing pilots to focus outside the window.
4. Advanced Navigation System:

• GNSS (Global Navigation Satellite System) for better location accuracy.
• RNP (Required Navigation Performance) up to 0.10 NM for precise route accuracy.
• FMS (Flight Management System) for efficient route planning.

5. Warning & Alert System:

• TCAS (Traffic Collision Avoidance System) to prevent mid-air collisions.
• EGPWS (Enhanced Ground Proximity Warning System) to avoid terrain and maintain safe altitude above ground or water.
• EICAS (Engine Indicating and Crew Alerting System) monitors engine and aircraft system performance in real-time.

6. Advanced Autopilot & Autothrottle: Reduces pilot workload and enhances aircraft stability with computer assistance and automation.

Every time I fly, especially when the weather is not favorable, I am always reminded of the power of nature and how small we are in the face of its grandeur. However, the advanced technology embedded in aircraft like the Boeing 737–800 Next Generation offers the best safety and efficiency in its class.

From the revolutionary wing design, fuel-efficient engines, to high-standard avionics, all are designed to provide a safe and comfortable flight. For airlines, this aircraft is cost-effective due to its efficiency, while for passengers, these technical capabilities ensure safety and comfort. In short, even in the midst of thick clouds and thunderstorms, I can pray and be confident that we are in one of the best “engineering marvels” resulting from the collaboration of science, technology, and human innovation. May your journey and flight be as comfortable and safe as this.

References

1. Boeing. (n.d.). Boeing 737 Technical Specs & Documents. Accessed via https://www.boeing.com/commercial/737ng
2. Boeing. (n.d.). 737 Airplane Characteristics for Airport Planning. Accessed via http://www.boeing.com/commercial/airports/plan_manuals.page
3. Federal Aviation Administration (FAA). (n.d.). Type Certificate Data Sheet (TCDS) for Boeing 737 Series. Accessed via https://rgl.faa.gov
4. CFM International. (n.d.). CFM56–7B Engine Overview. Accessed via https://www.cfmaeroengines.com/engines/cfm56-7b
5. CFM International. (n.d.). CFM56–7BE “Evolution” Upgrade. Accessed via https://www.cfmaeroengines.com
6. Aviation Partners Boeing. (n.d.). Blended Winglet & Split Scimitar Winglet Technology. Accessed via http://www.aviationpartnersboeing.com
7. Collins Aerospace. (n.d.). Enhanced Turbulence Radar (E-Turb) Technology. Accessed via https://www.collinsaerospace.com
8. Honeywell Aerospace. (n.d.). Weather Radar & Turbulence Detection Systems. Accessed via https://aerospace.honeywell.com
9. Airbus, Boeing, & Industry Data (reference for fuel efficiency comparison of aircraft). (2020). Fuel Efficiency Trends for Commercial Jet Aircraft.
10. Skybrary. (n.d.). Boeing 737–800 Specifications & Performance. Accessed via https://skybrary.aero/aircraft/b738
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12. Flightglobal / Flight International. (various years). Articles Related to Boeing 737 NG, Winglets, and Avionics Systems. Accessed via https://www.flightglobal.com