What Is MSL in Aviation?
Pilots · 5 min read
MSL stands for Mean Sea Level, a measurement of altitude that is used by pilots for both aircraft and drones.
A ravenous eagle hunting a salmon on shallow water resembles an A380 touching the runway and climbing back to the sky. Unarguably, both scenes are mesmerizing and jaw-dropping.
But there is some serious technicality in touch-and-go’s. We think it is time for a dive-in! Roll up your sleeves, here we reveal every bit of knowledge on the maneuver called ‘touch and go’.
During a touch-and-go landing (TGL), the aircraft continues the descent and the final approach like a normal landing.
The airplane touches down and rolls out along the runway reducing its speed. During the rollout, pilots reconfigure the aircraft settings for a takeoff and apply takeoff power just like a normal takeoff.
Flying a touch-and-go landing entails a higher level of proficiency – the maneuver goes beyond a normal landing and a takeoff.
Unlike a full-stop landing, a pilot has to focus more on a plethora of facts: when to add power for the takeoff, the remaining runway, other pilots flying in the vicinity, and many more.
A pilot flying touch-and-go’s sticks to a specific trajectory: a circuit or a traffic pattern. The pilot completes various legs of the traffic pattern when completing one circuit. Here are the main steps to be followed during a touch-and-go landing.
Step 01 – Takeoff: Identical to an everyday takeoff. The pilot enters the runway after completing the departure checklist and the briefing. Upon receiving takeoff clearance, the pilot applies full power to the engine(s) and initiates the takeoff roll.
Step 02 – Departure: The aircraft starts its climb to the Traffic Pattern Altitude (TPA).
Step 03 – Crosswind leg: During the climb, the pilot takes a right-angle turn and continues the climb to reach TPA (around 1,000 ft AGL).
Step 04 – Downwind leg: After taking the second right-angle turn to the downwind leg, the airplane continues to maintain its altitude flying parallel to the runway.
If flying at a towered airport, maintain contact with air traffic control. Regardless of the type or class of the airport, it is the pilot’s responsibility to watch for traffic and adjust the traffic pattern before entering the next leg.
Step 05 – Base leg: The aircraft descends to prepare for the approach. Along with the landing checklist, other settings such as flaps and engine power are adjusted during the base leg.
Step 06 – Final approach: Flying along the centerline of the runway. A pilot can use Precision Approach Path Indicator (PAPI) lights to maintain the correct approach vertical profile.
Step 07 – Landing: Upon reaching the aiming point, flare the aircraft to rest the main landing gear on the runway and reduce the power of the engine(s) to slow down the aircraft.
During the landing roll, with reduced speed, the effectiveness of flight controls will reduce and the pilot should be vigilant to maintain directional control as the aircraft should take off again.
Step 08 – Takeoff: Make sure the aircraft’s nose wheel is on the center line. Once the reconfiguration is done, apply full power for the next takeoff. This is the beginning of the second circuit. Positive aircraft control is the key as the aircraft inherits more momentum than a usual takeoff.
Normally, on a touch-and-go, the rolling speed is higher than usual. Hence, liftoff occurs prior to a normal take-off. Pilots should map a point to abort the takeoff should the aircraft could not gain the liftoff speed by the desired point.
On an ordinary landing, the aircraft activates Thrust Reversers (TR), wheel brakes, and speed brake spoilers to slow down and exit the runway for taxing. To perform a touch-and-go, pilots should reconfigure the aircraft for take-off.
The process is easier said than done. There is more to focus on and the slightest mistake will put the lives and multi-million-dollar aircraft in jeopardy.
Pilots apply slight braking to slow down the airplane and to buy more time for reconfiguration. As the aircraft is configured for landing, the following changes should be done:
• Flaps – change from landing position to take-off position.
• Re-trim – the aircraft is trimmed for the approach speed. Re-trim for climb speed.
• Carburetor Heat – Switch carb heat to OFF if it was ON during the landing to operate the engine with maximum power available.
The benefits of flying touch-and-go landings are manifold – eliminating extra flight time is considered to be the most imperative of all.
A pilot flying a touch-and-go landing does not waste their time like flying a full-stop landing. When flying full-stop landings, the aircraft comes to a full stop on the runway and exits the runway to taxi back to the holding point for the next takeoff.
Student pilots who have proven propriety by performing solo takeoffs and landings can perform touch-and-go landings with a flight instructor.
After a few practice flights, student pilots can opt to fly solo touch-and-go landings as the next step of their flight training.
Practicing touch-and-go landings is a vital part of any flight training. This helps pilots to understand how to perform a rejected takeoff and an aborted landing.
The experience gained through the training comes in handy in real-life scenarios to react fast and become an astute pilot.
The biggest burden of a student pilot is the cost of flight training- it feels like a student pilot has to spend a small fortune to complete his training.
But thanks to touch-and-go landings, the training intensity can be improved by performing multiple maneuvers in one sitting. The advantages of money savings are collateral – beneficial for both students and flight training schools and organizations.
Additionally, professional pilots need to perform touch-and-go landings to freshen their practice. Hence, authorities have included recurrent flight training programs. The training can be conducted with minimal time without disturbing the flight schedules.
Final Approach Fix (FAF) is as decisive as take-off and landing. A pilot who bungles at this point is more like inviting trouble. But, take note, that FAF is only applicable to non-precision approaches.
A pilot on a non-precision approach should keep an eye to maintain the correct altitude: flying too low or too high is not acceptable.
Flying in traffic patterns is considered to be the most effective way for mastering FAF. A relatively new pilot performing touch-and-go’s is more likely to sharpen his ability to correctly maneuver through the FAF.
Although touch-and-goes come in handy to craft a better pilot, there are certain restrictions when performing one.
To perform a touch-and-go or a stop-and-go, the runway length should be adequate- especially for a stop-and-go. Contaminated runways and ones with tailwinds should be considered inappropriate.
Short runways located at high-altitude airports are not suitable, either. Hence, do some research on the runway condition before planning for a touch-and-go training session.
Keep your hands off the fuel selector. If it is required to switch tanks, do not wait till the last minute. Downwind will offer a pilot ample time to do the switching.
Air traffic control should be aware of the intended maneuver to adjust the traffic accordingly.
Apart from the imperative change-over done by pilots to reconfigure the aircraft, communication with the air traffic controller is also a must.
As the takeoff is happening right after the landing, the aircraft should be at safe distance from other traffic departing from the airport to mitigate the effects of wake vortex turbulence.
If the conditions are not favorable for a touch-and-go, the controller will deny the touch-and-go request and ask the pilots to perform a full-stop taxi back.
Without performing a touch-and-go landing, the pilots can perform some other maneuvers to gain experience in the relevant phases.
A small time gap is introduced between the reconfiguration. Pilots come to a full stop following the landing and then do the reconfiguration while waiting on the runway.
Then starts the takeoff run from the point of stop. The downside of a stop-and-go is, that a longer runway is required for the maneuver. Additionally, the aircraft spends more time waiting on the runway- not suitable for airports with heavy traffic.
Starting with stop-and-goes can prepare a pilot for a full-scale touch-and-go without putting much stress on a student in the first place. Unlike a touch-and-go, the pilot is not busy with the reconfiguration when rolling down the runway.
The aircraft does not touch the runway. Normally, the aircraft descends to the Decision Height (DH) and maintain the altitude till the runway end. A low approach is different from a missed approach, as, on a missed approach, the aircraft starts to climb from the Missed Approach Point (MAPt).
The aircraft comes to a complete halt and taxis back to the holding position for the next takeoff. Consumes more time and fuel.
TOUCH and GOs are a maneuver more common in flight training than in commercial applications. The maneuver is dynamic and interesting to watch- the aircraft lands on the runway and takes off back to the sky.
During a touch-and-go landing, a pilot’s shrewdness is tested along with other cognitive skills. Reconfiguring from landing to takeoff is considered the crucial phase of a touch-and-go traffic pattern.
The dexterity gained by this maneuver will benefit both student and professional pilots to preserve the accolade- ‘Aviation is the safest mode of transportation in the entire world.