Philip nodded and said, "Okay." According to the quality and use of the aircraft, we choose a normal take-off wing load of 200 kg per square meter, then the wing area is about 36 square meters, the wingspan is 18 meters, the chord length is 2 meters, the aspect ratio is 9, the fuselage height is 2.5 meters, the ground clearance is 0.5 meters, the vertical tail height is 2.5 meters, and the total height of the aircraft is 5.5 meters. The cabin length is 5 meters, the baggage compartment is 2 meters long, the cockpit is 2.5 meters long, the entrance is 1.5 meters long, and the tail is 4 meters long, for a total length of 15 meters. We can use non-retractable front three-point landing gear, because the speed of the aircraft is not high, so the landing gear does not have a big impact on the flight speed, and the non-retractable landing gear can reduce the weight of the structure and improve the safety of landing. The main wheel base is designed to be about 3.6 meters, the front wheels can be turned, and the size can be selected with tires with a diameter of 450 mm and a width of 200 mm, which is convenient for take-off and landing at airstrips. ”

Philip said as he quickly scribbled the data down a piece of paper.

Messerschmitt looked at the data presented from Philip's pen, and a very beautiful business transport aircraft appeared in his mind, which is completely different from the common transport aircraft now, with a unique shape and very aerodynamic principles, Messerschmitt couldn't help but admire: "Not bad! Not bad! The prototype of this aircraft has been established, and we have to carry out a preliminary design of its control system. ”

Philip nodded and said, "This business transport aircraft is not very fast, so it is more appropriate to use a soft control system." Whether it is the main control system or the auxiliary control system, the use of soft control system has a natural advantage in structural design, it is much lighter than hard control, the structure is also simple, only need to use the tension of the steel cable and the pulley and bracket used to change the direction of the steel cable. In terms of the distribution of hand and foot control, I think that hand control is still responsible for controlling the aileron and elevator, while foot control is used to control the rudder, and the ailerons are operated by disc steering sticks, sprockets, steel cables, three sets of pulleys, fan rocker arms, and connecting rods. The elevator is operated by soft steel cables, tie rods, fan rocker arms, two sets of steel cables, 5 groups of pulleys, rear fan rocker arms and tie rods. The rudder is operated by soft steel cables. The auxiliary control system is used for the control of flaps, auxiliary flaps, elevators, and rudders. ”

Messerschmidt said: "Yes, this soft control system is lightweight, simple to manufacture, and more convenient to maintain, but it should be noted that in the specific design process, it is necessary to ensure that the pilot's hand and foot control actions conform to instinctive reactions and habits, the steering stick pushes the aircraft forward and the aircraft should bow its head, the steering stick pulls the aircraft up, and the aircraft should lean left to the left with the pressure bar, the left foot pedals the rudder, the nose turns left, the right foot pedals the rudder, and the nose turns right." Moreover, the disc steering stick should be able to operate the elevator and ailerons at the same time, and do not interfere with each other, the size of the rod force and rod displacement design is more important, and the rod force should be moderate.

Philip laughed, "Dr. Wiley said it so well. There are dozens of instruments, buttons, levers, and signal lights in the cockpit of the aircraft, and the pilot has to rely on the sense of his eyes, ears and hands to obtain information about the outside world and the instrument, and then quickly make a judgment, and immediately carry out correct control through the hands, feet and other motor organs, which is a very difficult operation process. At the same time, the high-altitude, high-speed, low-temperature and other environments in which the aircraft is located are also quite complex, which has high requirements for the performance of the aircraft and the quality of the pilot. As aircraft designers, we need to make the layout and design of the cockpit as ergonomic as possible, and even the design of the seats, which is related to driving. ”

Messerschmidt laughed: "This ergonomic concept is very good! Take the seat as an example, seat height, seat depth, inclination and headrest size all affect the piloting of the aircraft, and the layout of the instrument panel affects the driving efficiency. Of course, the climate control system is also very important, and I think that there should be a ventilation and heating system on board, which uses engine bleed air to warm the windshield in the cockpit and the driver's feet. There should be ram air inlets on both sides of the nose, which lead to the cockpit through pipes, and ventilate the cockpit by nozzles installed on both sides of the instrument panel with adjustable air volume and wind direction. There are 2 natural vents and 2 air outlets on the top of the cargo compartment. Cabin heating and cabin forced ventilation are optional. ”

Philip nodded and said, "Okay, let's do the overall plan of this commercial transport aircraft here, and I think the rest of the drawing work can be handed over to the designers of BFW." ”

Messerschmitt reached out and took a few pieces of paper full of files written in front of Philip, read them carefully, and then said with satisfaction: "Very good! I am sure that this solution will surprise our customers and give Junkers a look at the strength of our BFW." By the way, let's continue to complete the overall scheme design of the primary training aircraft. ”

With the basic idea just now, Messerschmidt also had no objection to the plan proposed by Philip, so the overall plan of the primary training aircraft was quickly determined.

According to the user's requirements, this beginner machine scheme uses a BMW 380 horsepower piston engine, equipped with turbochargers, 4-blade torque conversion propellers, tandem two-seater, retractable front three-point landing gear, the front landing gear is a pillar type, and the rear is included in the front fuselage. The main landing gear is a half-wisher type, with inward storage into the landing gear compartment of the center wing. Monocoque construction. The entire fuselage is an all-metal structure with a smooth appearance. It adopts an all-metal double-girder lower wing, which is divided into three sections: the center wing, the left wing, and the right outer wing. The central spar is fixed to the fuselage, and the outer wing and center wing are detachably connected, and the outer wing has a 10-degree upward reverse angle. The trailing edge of the wing is fitted with normal flaps and ailerons, and all handling systems are soft to handle.

Using the same methodology, the take-off mass of the Beginner Aircraft was estimated at 1,600 kg. The empty aircraft weighs 1,200 kg, including 300 kg for the power system, 650 kg for the structure and 250 kg for the equipment. The maximum fuel weight is 200 kg, and the maximum external weight is 100 kg. The wing area is 18 square meters, the wingspan is 10.25 meters, the height is 3.35 meters, the main wheel base is 2.95 meters, the estimated maximum range is 900 kilometers, the maximum level flight speed is 330 kilometers per hour, the cruising speed is 250 kilometers per hour, the endurance time is up to 4 hours, and the ceiling can reach 7000 meters due to the use of turbochargers.

By the time the two overall design plans were preliminarily completed, it was already more than five o'clock in the morning, and Messerschmidt and Philip were yawning again and again, looking at the two design plans, the two couldn't help but smile at each other. After a while, a wave of fatigue hit, and they both fell asleep on the table.