
Ejection Seat

40 ejections using a Mk8 ejection seat

Over 560 Mk8s currently flying in Tucano
Ejection Seat

40 ejections using a Mk8 ejection seat

Over 560 Mk8s currently flying in Tucano

Mk8 Ejection Seat
Following development of the highly successful Mk10 rocket-assisted ejection seat, a simplified, lightweight variant of this seat, designated the Mk8, was introduced for primary trainer aircraft, such as the Embraer Tucano. The most significant design simplification was the removal of the rocket motor to save weight. In most other respects, the Mk8 seat retains the excellent design features and functionality of the Mk10 seat. The Mk8 seat provides runway level escape at speeds down to 70 knots and has a maximum escape speed capability of 425 knots.
The Mk8 seat is currently in service in the Embraer Tucano, which is operated by the following countries: Angola, Argentina, Brazil, Colombia, Egypt, Honduras, Iraq, Kenya, Kuwait, Mauritania, Paraguay, Peru, United Kingdom and Venezuela. To date, there have been 40 ejections from a Mk8 ejection seat.
New Seat Installations & Retrofits
Looking to install a new seat into your aircraft? Let us help you find your perfect solution – check out our New Seat Installations & Retrofits page for more information.
Mk8 Ejection Seat
- Operating Ceiling: 50000+ ft (15,250m)
- Minimum height/Speed: Zero/70 knots in near level attitude
- Crew boarding mass range: 78.2 to 116.2 kg
- Crew size range: 5th to 95th percentile
- Maximum Speed for ejection: 600 KIAS
- Parachute type: GQ Type 1000 Mk 2
- Parachute deployment: Drogue assisted
- Drogue parachute type: 5ft
- Drogue deployment: Drogue gun initiated by trip rod
- Harness type: Combined
- Ejection seat operation type: Ejection gun
- Ejection gun: Single, two stage
- Gun stroke length: Variant dependent
- Ejection initiation: Handle on seat pan
- Electronic Sequencer: No
- Barostatic time-release unit: Yes + g-restrictor initiated by trip rod
- Automatic backup unit: No
- Manual override handle: Yes
- Timers: No
- Seat adjustment: Up/down. Actuator operated 28 Vdc
- Arm restraints: No
- Leg restraints: Yes, two garters
- Oxygen supply: Bottled emergency oxygen; Onboard oxygen generating system connection
- Personal survival pack: Yes
- Aircrew services: Oxygen (main and emergency) and mic/tel
- Command ejection: No
- Canopy jettison: No
- Miniature detonating cord: No
- Interseat sequencing system: No
Mk8 Ejection Seat
Featured in:
- Tucano
Mk8 Ejection Seat
- Seat firing handle is pulled, causing seat initiation cartridge to fire
- Harness retraction unit operated
- Primary cartridge fired causing inner and intermediate pistons to rise, releasing the top latch
- Secondary cartridges fire in turn as seat rises
- Electrical connections separate disconnecting seat actuator circuit
- Leg restraint lines draw back and restrain aircrew’s legs
- Leg restraint lines become taut and rivets shear, freeing lines from ejection gun cross beam
- Trip rods withdraw sears from drogue gun and barostatic time-release units
- Onboard oxygen and mic/tel disconnect
- Emergency oxygen trips
- After the delay mechanism has operated, the drogue gun piston fires
- Deployment of drogue stabilises and retards the seat and aircrew
Low altitude/high speed
- Seat descends stabilised by drogue
- Barostatic time-release unit completes run and fires
High speed/high altitude
- Barostatic capsule operates to prevent parachute deployment above pre-determined altitude
- Barostatic controlled g-switch delays parachute deployment above 8000ft until speed and g-force are reduced
- Barostatic time-release unit operates below pre-determined altitude, completes run and fires
- Manual separation (override) used if automatic system fails
- Gas from cartridge used to free drogue shackle link, release parachute mechanical lock, operate upper harness locks and lower harness release mechanism to free lower harness lugs, negative-g strap and leg restraint lines
- Drogue withdraws parachute from container
- Sticker straps momentarily hold pilot in the seat
- Parachute develops, lifts aircrew and survival pack from seat and pulls sticker clips from clips causing aircrew and seat to diverge
- Aircrew operates survival pack release strap which lowers survival pack on the drop line below aircrew – Normal parachute descent follows
Gallery
Mk8 Ejection Seat
Following development of the highly successful Mk10 rocket-assisted ejection seat, a simplified, lightweight variant of this seat, designated the Mk8, was introduced for primary trainer aircraft, such as the Embraer Tucano. The most significant design simplification was the removal of the rocket motor to save weight. In most other respects, the Mk8 seat retains the excellent design features and functionality of the Mk10 seat. The Mk8 seat provides runway level escape at speeds down to 70 knots and has a maximum escape speed capability of 425 knots.
The Mk8 seat is currently in service in the Embraer Tucano, which is operated by the following countries: Angola, Argentina, Brazil, Colombia, Egypt, Honduras, Iraq, Kenya, Kuwait, Mauritania, Paraguay, Peru, United Kingdom and Venezuela. To date, there have been 40 ejections from a Mk8 ejection seat.
New Seat Installations & Retrofits
Looking to install a new seat into your aircraft? Let us help you find your perfect solution – check out our New Seat Installations & Retrofits page for more information.
Mk8 Ejection Seat
- Operating Ceiling: 50000+ ft (15,250m)
- Minimum height/Speed: Zero/70 knots in near level attitude
- Crew boarding mass range: 78.2 to 116.2 kg
- Crew size range: 5th to 95th percentile
- Maximum Speed for ejection: 600 KIAS
- Parachute type: GQ Type 1000 Mk 2
- Parachute deployment: Drogue assisted
- Drogue parachute type: 5ft
- Drogue deployment: Drogue gun initiated by trip rod
- Harness type: Combined
- Ejection seat operation type: Ejection gun
- Ejection gun: Single, two stage
- Gun stroke length: Variant dependent
- Ejection initiation: Handle on seat pan
- Electronic Sequencer: No
- Barostatic time-release unit: Yes + g-restrictor initiated by trip rod
- Automatic backup unit: No
- Manual override handle: Yes
- Timers: No
- Seat adjustment: Up/down. Actuator operated 28 Vdc
- Arm restraints: No
- Leg restraints: Yes, two garters
- Oxygen supply: Bottled emergency oxygen; Onboard oxygen generating system connection
- Personal survival pack: Yes
- Aircrew services: Oxygen (main and emergency) and mic/tel
- Command ejection: No
- Canopy jettison: No
- Miniature detonating cord: No
- Interseat sequencing system: No
Mk8 Ejection Seat
Featured in:
- Tucano
Mk8 Ejection Seat
- Seat firing handle is pulled, causing seat initiation cartridge to fire
- Harness retraction unit operated
- Primary cartridge fired causing inner and intermediate pistons to rise, releasing the top latch
- Secondary cartridges fire in turn as seat rises
- Electrical connections separate disconnecting seat actuator circuit
- Leg restraint lines draw back and restrain aircrew’s legs
- Leg restraint lines become taut and rivets shear, freeing lines from ejection gun cross beam
- Trip rods withdraw sears from drogue gun and barostatic time-release units
- Onboard oxygen and mic/tel disconnect
- Emergency oxygen trips
- After the delay mechanism has operated, the drogue gun piston fires
- Deployment of drogue stabilises and retards the seat and aircrew
Low altitude/high speed
- Seat descends stabilised by drogue
- Barostatic time-release unit completes run and fires
High speed/high altitude
- Barostatic capsule operates to prevent parachute deployment above pre-determined altitude
- Barostatic controlled g-switch delays parachute deployment above 8000ft until speed and g-force are reduced
- Barostatic time-release unit operates below pre-determined altitude, completes run and fires
- Manual separation (override) used if automatic system fails
- Gas from cartridge used to free drogue shackle link, release parachute mechanical lock, operate upper harness locks and lower harness release mechanism to free lower harness lugs, negative-g strap and leg restraint lines
- Drogue withdraws parachute from container
- Sticker straps momentarily hold pilot in the seat
- Parachute develops, lifts aircrew and survival pack from seat and pulls sticker clips from clips causing aircrew and seat to diverge
- Aircrew operates survival pack release strap which lowers survival pack on the drop line below aircrew – Normal parachute descent follows