Introduction

Considering the 86 year history of the racing, the formula one racing class is one of the most successful genres of all aircrafts.  In a life time of the half century, a large number of the races, pilots and airplanes have been seen. Formula 1 racing aircraft named Sharp Nemesis is the one of the aircraft class that has been recognized at international level and exported from United States to Europe. The federation of aeronautics has announced the vehicle as world’s best competitive vehicle in the aviation history. In the community of air racing the Sharp Nemesis has its inceptions in many wiser head concerns. According in Nemesis Air Racing Team, this aircraft has been one of the most successful in the air-racing history. However the sport has been found to be strangled due to the excessive costs and accidents at unacceptable level.

Participating in of the National Championship Air Races requires that the participant must follow the set of rules outlined by the management committee. These rules are revised and updated online. These regulations allow the participants to compete fairly and safely. For this case study, the Nemesis aircraft has been selected and it will be designed in accordance with the International Formula One Technical Rules

Figure 1- Source: National Air and Space Museum

Aircraft Set-up

The aircraft designing for the competition purposes requires the development of relevant specifications which have to be achieved by conducting some technical solutions. Full specifications of the aircraft designing require the performance parameters to be defined. The whole design of the Sharp Nemesis has been found to be dominated by the low signatures and dedicated stealth of the aircraft. The development of an aircraft project requires performance parameters as strong drivers. The performance parameters can be divided into various categories according to the design requirements including Point performance parameters and Mission performance parameters. The aircraft setup of the formula one racing class i.e. Sharp Nemesis will be designed in line with following specifications.

Aircraft Engine Setup

Research has shown that only 0-200 or C series engineers are suitable for Formula One racing. The contestants are required to use the Teledyne Continental factory and other officially approved parts. Typically, the C series engines are modified by the use of approved parts to ensure same horsepower as the 0 – 200 engines. The Formula 1 rules allow an engine worker or a builder to replace or modify part of parts of the vehicle but effectively, the basic approval of some of the parts is nullified.

Typically, the design locations include the carburettor as well as the induction system. The original studs are to be used to mount the spider. The height of the spider is to be less than or equal to 3 inches or 26 mm. This height is measured to the top of the case stud flange and from the carburettor mount flange. Exhaust and intake elbows are mounted on the actual manufacturer’s position studs. The factory may choose to weld and remove to the intake premier pads to meet the design needs. All exhaust and intake parts are allowed to be smoothened over.

Carburettor Details

The carburettor can be modified in the areas listed below and only Marvel MA 3 SPA type models are to be used.

• Float level will be altered/modified as per designers recommendation
• Casting for fuel and air will be smoothened over
• The main fuel discharge nozzle will be allowed. This will include drilling to a maximum 0.01 inch or less in diameter
• Seats and needle will be as per the approved parts.
• The accelerator pump should operate as it does normally. The discharge tube can be cut down to 0.75 inches at the max.
• Depending on the needs of the design, electric fuel pumps can be utilized.

For information on carburettor dimensions, Formula 1 website can be visited that has published a detailed report on dimensions specifications and requirements. 

Crankcase Type

The width of the crankcase can be variable depending on the wear and other factors. This problem can be resolved with the use of shims to adjust clearance volumes. Bolts may be used to strengthen the C series engine crankcase. This can be achieved by drilling through the centre main bearing flange of the crankcase. The crank case breather should be placed open to the outside.

Cylinders:

1. Only the licensed version of 0-200 cylinders or Teledyne Continental C series engine will be used
2. According to the F1 rules, the maximum volume of the cylinder is 135 cc. This volume, however, is measured with the piston at top dead centre
3. The swept per volume cylinder shall be less than 837 cc
4. The inside diameter of the valve seat inserts should be less than or equal to 1.45 inches for exhaust and 1.58 inches for the intake

Pistons Type

Pistons of FAA PMA 0-200 and Continental C series type will be allowed by Formula 1. According to the rules, there should be no less and no more than four ring grooves and each groove will carry at least one ring piston. F 1 has placed no restrictions on the use of pistons except for the minimum weight.

Smoothing effect

Formula 1 allows for smoothing of all external and internal forged and cast parts. Oil lubrication hole, clearance or fit may be performed in the engine to balance the excessive heat. See F1 International technical rules for further details.

Camshaft Specifications

The F1 technical specifications should be taken into account when using any FAA PMA or TMC stock camshaft. The manufacturer is allowed to measure at the exhaust valve and the intake. The intake reading will ream within the specified profile while starting at 40 deg. BTC. Similarly, measurement for the exhaust will start after tope dead centre at 95 deg, whiling staying within the specified profile.

 Valve Springs use

No restrictions are placed on retainer washers, shims, valve springs and spacers. Only recommended and approved matching hardware and continental springs are to be used. Most suited Ignition Systems of electronic or magneto ignition system will be used for the aircraft. There is no restriction on the type of spark plugs and ignition routing and harness.

 Performance parameters

The point performance parameters are required for the singular items and needed to be satisfied for a fixed aircraft setup at a particular design point. The mission performance parameters are needed when the aircraft setup is considered with the mission context i.e. steady change in the fuel mass. There are comprehensive systems of formulae for both performance categories which have been used and published by NASA. These parameters are illustrated in detail in following sections (International 2007).

Point performance parameters

Point performance parameters for Sharp Nemesis are used to define a single payload or fuel situation including

• Stall speed for the determination of the load factor sustainably
• Take off run length for the determination of the excess power specifically
• Turn rate for the determination of the run length of landing

Mission performance parameters

Mission performance parameters are used to present the parameters of the Sharp Nemesis setup performance with the context of aircraft mission

• Payload mass use to determine the rate of plane climbing with the context of aircraft mission
• Range of the flight for the determination of the plane acceleration
• Altitude of the aircraft for maneuver determination
• Speed of the aircraft

Part’s Weights Specifications

Weights of the parts are to be no more than the limits provided by Formula 1 Technical Rules. Therefore it is expected to lighten the parts to these limits to be able to participate in the racing.

1. The weight of the FAA PMA pistons or Continental cast pistons is to be no more than 670 grams. Wrist pin with end plugs and pistons with rings must weigh no more than 965 grams. The total weight for all four piston assemblies shall not exceed 3865 grams limit.
2. Maximum weight limit for forged pistons with end plugs and wrist pings is 877 grams. Custom forged pistons shall not exceed 610 grams in weight and therefore the total of four assemblies should weigh less than or equal to 3508 grams.

It is recommended to be very careful when ordering over sized pistons to protect the cylinders. Furthermore, specifications for swept volume must be satisfied at all times.

For more information, Formula 1 website can be visited that has published a detailed report on the weight limits for various parts of the engine.

 Usage of Fuel

Available from an onsite source, the standard and pure aircraft fuel shall be used by the manufacturers. The F1 strictly prohibits mixing of any kind to the fuel, air or fuel/air in the engine. The F1 team may take a fuel sample at any time. The same, however, will be taken from a practical and logical point in the fuel system. The Technical Committee may choose to analyse the sample at the approved facility to determine any discrepancies. Any auxiliary or inaccessible tanks in the system will be made unavailable by obstructing the flow. Starting may be enhanced by the use of certain products that are applied to outside of the carburettor inlet scoop.

 The Oil System

The oil system operations will be performed in an approved and recommended style. The oil pump system in the oil shall not be supplemented with the use of auxiliary oil systems.

For more information, Formula 1 website can be visited that has published a detailed report on the engine oil system requirements.

 The Aircraft Weight

The empty airplane will weigh at least 227 kg in weight without oil or fuel added to it. The Pilot should not weight more than 160 pounds as per the requirements of Formula 1. The manufacturer will be allowed to satisfy the minimum weight requirements by using ballast. The ballasts will be placed within 305 mm of the seat position.

Propellers and Wings

For each operation, the propellers should be fixed pitch. The use of single aluminium alloy propellers is prohibited for any flight at the racing area.

The wing area of no less than 66 square feet will be used. The wing area does not take into account the stall strips and fillets but include the area displaced by the fuselage. Flaps may be incorporated in the design but they wing area will be measured with these flaps pulled in. The ailerons will be perfectly balanced in the in a dynamic manner. Only approved method of achieving static balance will be used.

 Landing Gear

1. The main landing gear are to be fixed and non retractable.
2. Wheels brakes will be installed and tested
3. There will be two metal wheels on the aircraft. The standard dimensions for tires are 11.4 x 5 type, with tires touching the ground.
4. Wheel fairings or pants should not exceed 6.5 inches in width internally. An infinite access for brake and wheel inspections should be made provided by the fairings or pants.

Pilot Vision and Other Specifications

As per the design and the necessary requirements, the vision of the pilot when wearing all the safety equipment must be able to scan; 5 ° down over-the-nose, 25 ° straight down the non-canard leading edge wing, 45 °C vertical and 270 °C horizontal visibility. Fuel Tank will have the capacity of more than 5 US Gallons. The cockpit will have room for crash helmet and a parachute, seat belt and shoulder-harness as per National Championship Air Races standards. The vertical dimension (outside) at cocktail shall be more than 76.3 cm, with centre of gravity being between 8 to 25 percent of MAC of wing.  The cockpit will be designed to open from both inside and outside

Design Performance

Most of these performance parameters have not been reflected immediately through the performance models of the formula one racing class i.e. Sharp Nemesis. The performance characteristics include the requirement of the specified models through technical solutions.  The technical solutions will be sorted out by the evaluation of the effects which are quantifiable i.e. boundary conditions like drag. The requirements for the required performance of the formula one Sharp Nemesis have to be compatible with the vehicle specifications. Specific formulas and equations are required to develop such aircraft setups. The refueling capability of the specified formula one racing class can be translated to the specific subsystems and a refueling probe which has its own drag and mass properties, by the integration of the specific performance parameters. The overall configuration of the aircraft can be defined through various restrictions that can be faced during designing stages. For such purposes, the extensive performance models are required which can be used as a guide for formula one racing class (International 2011).   

Figure21- Source: National Air and Space Museum

References

1. International Formula One Procedure Rules (2007) PREPARED BY INTERNATIONAL FORMULA ONE PYLON AIR RACING INC. [Available online at] :< http://www.if1airracing.com/index_htm_files/IF1_Procedure_Rules_8-07-07.pdf> Accessed 15 April 2013
2. International Formula One Procedure Rules (2011) PREPARED BY INTERNATIONAL FORMULA ONE PYLON AIR RACING INC. [Available online at] :< http://www.if1airracing.com/index_htm_files/IF1_Technical_Rules_Rev2011.pdf> Accessed 15 April 2013
3. Len A. (2002) Basic setup for aircraft using 2 channels and 2 servos each for ailerons, elevators and rudders, [Available online at] : <http://s7d5.scene7.com/is/image/horizonhobby/1169-basicsetup>Accessed 15 April 2013
4. NMPRA (2011) Electric Formula One Rules, [Available online at] <http://www.nmpra.org/rules/EF1NewRules_5_%5B1%5D.pdf> Accessed 15 April 2013
5. Universal (2013) Improving airplane performance, [Available online at]: <http://www.rcflightschool.com/Inter_LessonsPDF/Inter_0A4-13.pdf> Accessed 15 April 2013