Cart Shopping Cart My Store Account Orders Downloads Shopping Cart “13. Will Accessories Impede Our Payload?” has been added to your cart. Continue Shopping “7. Predetermination of Weight Efficiency” has been added to your cart. Continue Shopping “23. The Value of a Pound” has been added to your cart. Continue Shopping “12. Weight Control – Aircraft Design Problem” has been added to your cart. Continue Shopping Remove item Thumbnail image Product Price Quantity Subtotal × 13. Will Accessories Impede Our Payload? $20.00 13. Will Accessories Impede Our Payload? quantity $20.00 × 7. Predetermination of Weight Efficiency $20.00 7. Predetermination of Weight Efficiency quantity $20.00 × 23. The Value of a Pound $20.00 23. The Value of a Pound quantity $20.00 × 12. Weight Control - Aircraft Design Problem $20.00 12. Weight Control - Aircraft Design Problem quantity $20.00 Coupon: Apply coupon Update cart Available coupons (Click to apply). Cart totals Subtotal $80.00 Tax $0.00 Total $80.00 Proceed to checkout