 Now, one more option that you have and you see sometimes is a three-surface layout or a three-surface aircraft. Now the question that somebody will ask is that if you can make a design with only two surfaces then why use three surfaces because it adds cost, it adds weight and it give you larger wetted area. So in a three-surface layout as can be seen in this picture you have one surface in the front which is a canard, the second one which is the wing and the third one which is the tail. This is why we call it as a three-surface layout. So obviously there must be some benefit and the principal benefit is that because there are three surfaces you are able to trim the aircraft with near minimum drag over a much wider centre of gravity range because you can load or unload each of the two extreme surfaces to allow creation of the moments required to balance about the centre of gravity. And secondly if you do it very carefully and if you design it very carefully efficient component integration can actually save weight. If you notice in this picture for example the wing of this aircraft PRGO P180 Avanti seems to be a much slenderer and smaller compared to a typical wing that would be needed for an aircraft of this particular type. So this particular aircraft GP-180 has earned the epitaph of the Ferrari of the skies. This is an image of the aircraft taken from the bottom and many people would think that this aircraft is flying from right to left because they see the engines mounted in that fashion but actually it is flying from left to the right. So I think it is very important for us to get familiar with this very interesting aircraft. It is one of my favourites. So I thought it is better we watch a short promotional film about this aircraft. The original Piaggio Avanti P180 twin turboprop pusher first flew in 1986 and was certified in 1990 yet this 2001 model still looks as futuristic as it did more than a quarter of a century ago. Perhaps unsurprisingly this aircraft is still ever manically in a class of its own. The small forward lifting wing means that the rear horizontal stabiliser is also a lifting surface resulting in a 34% decrease in main wing area even the fuselage itself is shaped out of the aircraft's total lift. The narrow cord wing ensures that the laminar flow is maintained around 50% of wing cord compared with around 20 to 25% of conventional tractor turboprops where the propeller wash disturbed the airflow over the wing. An underlying reason for its ability to maintain laminar flow is the quality of the surface finish. Although the Avanti is 90% aluminum alloy the fuselage and wing look like they are moulded in composites because they are constructed with airframe panels held in place in the jig during assembly by large vacuum pads so that the frame and the ribs can be riveted from the inside. This makes for an exceptionally smooth finish and reduces drag. The result is that the Avanti offers superb performance for a turboprop, a cruise ceiling of 41,000 feet with a cabin altitude of only 6,600 feet cruising around 350 360 knots in the high thirties with a fuel burn less than 300 pounds per side and a range of close to 1450 nautical miles which means you can fly 1,000 nautical miles in a little over three hours burning just 1,600 pounds of fuel. The aircraft is certified to category two instrument landings, steep approaches and flight into known icing and the Avanti has the ability to operate on short runway lengths of only 1,070 meters at maximum weight. This airframe has also been recertified to increase maximum takeoff weight of 12,100 pounds allowing extra two passengers at the maximum fuel load. The cabin provides a stand-up height of 1.75 meters and a width of 1.85 meters, dimensions only better by super mid-sized jets. The cabin can seat up to nine in a corporate shuttle layout but typically seat six in this VIP role with an aft toilet. The Avanti is certified for single pilot operation. The Avanti is a DC electrical aircraft with no A to U but you can use an external power cart to load the FMS prior to start. All engine start and run switches are centrally located in one panel at the forward end of the centre console just ahead of the throttles. A rotary test switch on the base of the console is used to check all ancillary systems such as hydraulics, electrics and de-ice and the aircraft can be ready to taxi in three to four minutes after ending the start. The avionics include weather radar, traffic avoidance and tours. In addition to 8.33 MHz VHF radios, precision R-NAV and VNAV, this P180 also has the optional HF radio. Whilst the AGM has introduced its avionics upgrade of the P180 Avanti 2 tovo prop pusher, the Avanti 1 remains a captive proposition with its mode appreciation combining with perfect cabin and low operating cop. The Avanti has no natural turboprop competitors, its closest jet rival being the Rating Premier 1 and Cessna Citation CJ1 and 2. If pure top speed is not the overriding criteria, the Avanti's combination of fuel efficiency, cruise speed, range, ceiling and cabin size are hard to beat. The aircraft deserves its Ferrari of the skies title and can hold its own against any similar size jet. So that was about the Ferrari of the skies. What are the design features of this aircraft which make it very distinctive? First of all it has high aspect ratio wings as you can see in this picture, very slender wings and the engines are mounted behind the pusher engines which result in a very quiet cabin. It has got an hydral in the canards, you can notice here, one can notice here that the canards are mounted at a slight 2 or 3 degree downwards angle. We also see that the canards has flaps, it is very clear in this particular figure that these canards have flaps, you can see here. You have delta fins on the aerofoil shaped fuselage. So the fuselage itself is very beautifully shaped as you can see, it is shaped like an aerofoil and you have these delta fins. These fins enhance its lateral stability characteristics and interestingly the passenger cabin is mounted ahead of the wings. The wings are mounted behind the passenger cabin and the engines are mounted behind the wings. So you have unrestricted view for the passengers, you know the view that is available to the passengers is completely unrestricted on both sides plus the location of the engines behind results in very low noise levels. Thanks for your attention, we will now move to the next section.