Tires Protector

DEVICE FOR PRE-ROTATION OF AIRCRAFT’S GEARS PRIOR LANDING

Landing of an airplane without pre-rotation of the gears has touch acceleration causing tires damage:

Landing of an airplane with pre-rotation of the gears has no touch acceleration diminishing tires damage:

MODUS OPERANDI

This outstanding innovation brings completely new concept in aviation and directly increases the profit of airliners and airports too.

This innovation significantly increases endurance of the landing gear’s tires making them also more resistant to defect. This innovation significantly extends the total safety of an aircraft during landing procedure.

The interval between tires replacement is significantly extended which increases the number of the flights with no mid-flight replacement which is very important on short and frequent flight routes.

This innovation directly increases profit of an airliner by reducing costs on tires, reducing service time and costs for replacement and by increasing operational effective time of an aircraft.

BRIEF DESCRIPTION OF THIS INNOVATION

Picture 1 shows layout drawing of elements of the device in the basic version:

14 - Main gear electric motors with rpm counter,

15 - Intelligent drivers/controllers of the electric motors,

16 - Power cables for main gear electric motors,

26 - Nose gear electric motors with rpm counter,

29 - Power cables for nose gear electric motors.

Fig 1

Figure 2 shows disposition of elements of the device in the basic version:

Top of the page – master switch and malfunction warning lights placed in cockpit
Bottom left – nose gear with mounted electric motors and transmission showed from the back.
Bottom right – main gear with mounted electric motors and transmission showed from the back.

Fig. 2

The device operates according to a certain algorithm. When lowers landing gear is down and locked, the information is transferred to each pair of intelligent drivers/controllers. These intelligent drivers/controllers then provide power supply to appropriate electric motor which then accelerates wheels to the landing speed via transmission system. After first contact with runway is obtained the contact indicators send information to the intelligent drivers/controllers to cut motors’ power supply. This ends the procedure’s cycle. New cycle is activated with the next time when the landing gear is lowered and locked.

CALCULATION OF THE MOTOR’S POWER

This innovation might be very simple by usage of brush and brushless DC motors. This particular case the controller itself is simple PWM one and the motors are working only in predefined small interval of powers. Only the one controllable parameter is used when the DC motors are utilized and this is variation of driving voltage according the landing touch speed.

Required power of the electromotor on the main landing gear is given by the following equation:

(1)

Whereas:

W	=	required power of the particular electromotor, and the total power is proportional to the number of aircraft’s wheels.
m	=	mass of a wheel,
v	=	peripheral speed of the wheel during the contact with runway (landing speed),
t	=	acceleration time of the wheel from zero to the landing speed.

Required power of the electromotor on the nose landing gear:

(2)

Variables have the same nomenclatures as in the previous formula.

Attention: This invention is copyrighted since 2005.
Any unauthorized usage is prohibited.

All inquiries should be sent to author:

Dipl.El.-Ing. Andrija Radović

E-mails: andrijar@gmail.com, andrijaradovic@hotmail.com or andrijar@andrijar.com.

Tel: +381 64 1404075 or +381 61 7202676