Team Members: Lovedeep Bhela, Sam Dubin, Karah Oliver, Cody McMillen, Parth Patel, Yash Soni

Abstract The report introduces the initial conceptual design of a high efficiency transport aircraft. The

analysis is based off of technical requirements and relative constraint diagrams generated from data that was collected from similar heavy lift aircraft in order to produce a preliminary sketch.

I. Design Problem

Team Griffin must design a highly efficient aerial transportation vehicle that

should have the capacity to haul heavy loads over a large distance. The design

concept performance capabilities must include a high payload weight with an

efficient cargo space configuration. The aircraft is expected to have maximized

range and endurance as the result of an optimized aerodynamic design.

II. Design Requirements

The two driving design requirements for the transport aircraft include high

payload weight and long range. The 747-8F was chosen as the aircraft which these

requirements were based off of: at least 113,000 kg of payload and at least 11,380

km of range. Other parent aircraft referred to for comparison were:

Lockheed Martin C-5 Galaxy

Boeing 747-8F

Boeing 777-F

Airbus A380F

Antonov An-225

From these parent aircraft, the derived design requirements were compared and

validated as seen in figure 1. A secondary design requirement for the transport

aircraft is efficient cargo storage. Currently, the 747-8F uses LD-1 containers to

load cargo and so the storage configuration for this transport aircraft must match

or exceed this design. This approach will drive the shape of the cargo area and

fuselage.

III. Design Constraints

In order to meet the requirements, constraints were established as presented in

table 1. The requirements and constraints are dependent on each other. For example, if

the wing area of the aircraft were to be increased the range would increase. The

constraints are defined through the analysis of similar aircraft which meet the

requirements. The design values were calculated by averaging the values of the aircraft

and applying the respective formulas. These constraints are going to define the design

and performance of the aircraft.

Table 1. Design Constraints

Design Variable Value Units

WTO 326,383 kg

Wpayload 113,000 kg

vstall 61.2 m/s

dTO 2,500 M

Range 15,000 km

S 600 m2

L/Dmax 16.547 -

W/S 5,000 Pa

T/W 0.25 -

We/WTO 0.452 -

Wf/WTO 0.20176 -

IV. Figures

Figure 1.Constraint diagram plotting wing load versus thrust to weight ratio.

The Griffin aircraft lies near the center of the competitors’ aircrafts in figure 1.

With a thrust to weight ratio (T/W) of 0.252 and a wing loading (W/S) 5,000 Pa, the

Griffin’s constraint diagram values resemble the C-17’s the closest.

0 2000 4000 6000 8000 100000

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

W/S

T/W

Constraint Diagram

C-17

C-5

Beluga

747-8F

777F

Md-11

A-380F

An-225

Griffin

Figure 2.Plot comparing short, long, and average range by plotting maximum takeoff weight versus lift to drag ratio.

Figure 2 shows that for higher values of takeoff weight, the lift over drag ratio

decreases. For each L/D value the long range curve shows that for longer range the

aircraft has the highest takeoff weight. As L/D increases the takeoff weights for each case

all appear to converge to a similar value around 2,500,000 N.

Figure 3. Comparing Parasite, Induced, and Total Drag at different velocities.

Figure 3 above illustrates total drag in relation to velocity. The blue curve

represents the parasite drag. The red curve represents the induced drag. It can be noted

that the parasite drag increases proportionally to the velocity squared. It can also be

0

1,000,000

2,000,000

3,000,000

4,000,000

5,000,000

6,000,000

7,000,000

0 5 10 15 20 25 30

WO

L/D

MTO vs. L/D

Short

Average

Long

0

100000

200000

300000

400000

500000

600000

700000

800000

900000

1000000

0 100 200 300 400

Dra

g [N

]

Velocity [m/s]

Drag vs. Velocity

Parasite

Induced

Total

noted that the induced drag is inversely proportional to the velocity. The green curve

represents the combined drag. At velocity we of 139 m/s, the lowest total drag can be

accomplished.

Figure 4. Plotting lift to drag ratio vs. lift coefficient.

The figure above illustrates the lift over drag ratio in relation to the coefficient of

lift for Griffin aircraft. The Griffin aircraft will have a coefficient of lift of 0.66. This will

provide with an optimal lift over drag ratio of 16.55. This is important as it will affect the

fuel economy and climb performance.

V. Aircraft Specification Table

Design Variable Value Units

WTO 326,383 kg

Wpayload 113,000 kg

vstall 61.2 m/s

dTO 2,500 M

Range 15,000 km

S 600 m2

L/Dmax 16.547 -

W/S 5,000 Pa

T/W 0.25 -

We/WTO 0.452 -

Wf/WTO 0.20176 -

0.00

2.00

4.00

6.00

8.00

10.00

12.00

14.00

16.00

18.00

0 1 2 3 4 5 6 7 8 9

L/D

CL

L/D vs CL

VI. Conceptual Aircraft Sketch

Figure 5. The side and front view of Griffin Aircraft based on 747-8F with increased wing span.

Figure 6. Top view of Griffin Aircraft.