Hiiraan Online

by Dr. Ibrahim Abikar Noor
Friday July 14, 2023

Halla Airlines plane that veered off the runway during landing at Aden Adde International Airport

This writing looks at few types of airplane landings and weather conditions that could pose challenges. I will then offer recommendations and end with a concluding thought. However, before going deeper into my writing, a short disclaimer is in order. This article is not based on investigations of the crashes or statements from the crew of those airplanes, but on reflections of this author’s personal experience flying in and out of Aden Adde International for a decade as well general concept of flying.

Takeoff and landing are the most critical phase of flight operation. In takeoff, thrust is maximum where fuel consumption is much higher than when the plane is at cruising altitude. During takeoff, pilots are on high alert to the possibility of engine failure which can be fatal if corrective action is not taken immediately. Similarly, pilots are very much focused on keeping the aircraft aligned on the runway and maintain correct glide path during landing.

Having watched the videos of crashes at Aden Adde international, both planes landed on Runway 05. Aden Adde International has one runway with 05 and 23 designation. To my non-aviator friends, the numbers represent runway magnetic degree which is compass heading corrected for deviation. For example, if wind is coming from north heading south, pilots fly parallel close to the coast to land to north-runway 05. Conversely if there is southerly wind at the airport, pilots use runway 23. In other words, fly over the city and land toward the sea touching down by the Somali Airforce camp-Aviazione.

Runway 05. Aden Adde International Airport, Mogadishu

Coming in for landing or taking off, pilots need to know the wind direction and speed. This information is given to them by the ground controller or tower. To naked eye, the first crash seemed to have landed the beginning edge of the runway, and immediately after, one of the main landing gears collapsed. The second crash also landed very close to beginning of the runway, and like the first accident, a main landing gear collapsed. Both planes were using runway 05. From this we can elucidate the wind direction given to the cockpit crew was a northerly wind direction. With that background, here are few points to ponder:

50 feet over runway threshold.

Pilots need to cross runway threshold at 50 feet high. Threshold is the beginning of the runway and is clearly marked with several long parallel lines visible to pilots when they are close to landing (see the photo above). Additionally, big jets have radio altimeter that reads out loud when the plane is coming in for landing. A voice prompt reads and one thousand, five hundred, one hundred, and fifty feet. The airplane should be crossing the threshold when the radio altimeter voice prompt sounds “Fifty”- meaning fifty feet high. Granted small aircrats are not equipped like big airplanes, pilots need to plan to go over threshold at or close to 50ft altitude.

Over obstacle approach, Short field and crosswind landing.

The landing phase is one of the most difficult maneuver pilots undergo during initial training since all landings are not the same. The training covers how to approach the runway when there is high train or obstacle close to the runway threshold. Precautions are taken to stay clear of barriers. Training manual almost always cover short field landing. In this case, 50 feet over threshold does not apply since the runway is short. Landing can be aimed at the beginning of the runway to ensure enough runway distance is available for the plane to stop. Mogadishu runway is long enough for most planes. Thus, no need to execute short field landing technique.

Crosswind landing is another exercise that is part of student training. This phenomenon is when wind is blowing from side angle to the runway instead of head-on making difficult to align the airplane on the runway centerline. Each airplane has a designated maximum crosswind speed where pilots are expected to go to alternate runway, or to another airport if crosswind maximum is over the particular aircraft’s specification. Such is the case with Mogadishu in high crosswind speed situation because of the single runway.

Windshear

This is a weather condition where wind suddenly changes direction and speed. Low altitude windshear is usually caused by thunderstorms or obstacles-including constructions-in the vicinity of the runway. Windshear can push the airplane vertical (up or down), or sideways, and is dangerous during landing as the airplane is close to the ground. Airport controller, tower, or other pilots advise approaching airplanes of this dangerous weather condition.

Recommendations

The aim of this writing is to shed light on challenges cockpit crew experience during landing. The 2 crashes in 2022 and 2023 on runway 05 at Aden Adde international should serve as a) lessons learned, and b) an opportunity for improvement. Here are few points that could contribute to the safety of flight operations. This suggestion is more catered toward the landing phase.

• Runway lights such as Visual Approach Slope Indicator (VASI), and Precision Approach Path Indicator (PAPI) are set of lights that orient pilots during landing. PAPI, are four lights located on the left side of the runway. These lights inform pilots whether their approach is high (4 white lights), low (4 red lights), or on correct glide path (2 white and the rest 2 red). See diagram below. 

• Another tool widely used in main airports-including our neighboring countries-is Instrument Landing System (ILS). This is a precision radio navigation system on the field that helps pilots maintain correct vertical and horizontal path toward the runway. Most airplanes are equipped with ILS instrument that receives the radio signal to help maintain correct glide path. ILS is extremely important during low visibility and night time. (See diagram below).

• Acquiring modern Meteorological equipment is important to help inform pilots of mother nature dangers such as windshear, turbulence, thunderstorm at enroute and approach, and crosswind strength.
• Consistent, well-put staff and leadership trainings are equally important to maintain employees current on technology use, aviation policies, communication, evaluative thinking, and information sharing endeavors.

For an old airport with limited space to possibly build another runway albeit increasing flight operations, resource alignment is necessary for Aden Adde international to meet the demand and stay competitive. In less than a year, a combined 70 souls onboard were involved in the crashes of Fokker 50 and Embraer 120. This could be a national security crisis in the making if current trend holds. It needs to be addressed as such using competent manpower and cutting-edge technology. Looking into the different funding streams of the country’s civil aviation industry, and more appropriations from government’s general fund (if any) could be one revenue source to help with shortcomings. Additionally, engaging private sector for the common good is equally important. The Somali aviation industry has seen tremendous improvement in recent years as evidenced by the increasing airline companies interested to start operations at Aden Adde International. Yet more is needed in safety and quality. Above all, is there a nominal dollar value on human lives?