Blackhawk

2003
Black

The Blackhawk was designed to compete in the 2002/2003 AIAA/Cessna/ONR Design/Build/Fly contest held in Ridgely MD, in April of 2003.  The objective was to fly two different missions: a missile decoy mission in which the aircraft carried a large external payload, and a sensor deployment mission in which the aircraft remotely deposited a payload on the runway.  The mission score also depended on a timed task in which the aircraft which was initially stored in a 4'x2'x1' box, had to be assembled as quickly as possible.  Aircraft were subject to several design constraints such as runway length, wing span, battery type and size, motor type, etc.  The Black team finished in 5th place overall at the contest.

Specification List: 

Wing

  • Wingspan:        7.75 ft
  • Wing Area:       8.75 ft
  • Aspect Ratio    6.86
  • Airfoil:                Eppler 423

Fuselage

  • Length:    5.25 ft (Tail boom installed)
  • Height:    8 in

Propulsion

  • Motor:         Astroflight 640S with gear ratio 1.31:1
  • Controller:  Astro 204D
  • Fuel:           24 SR 2400 NiCd batteries
  • Propeller:   18 in

Weights

  • Empty Weight (Without batteries):    9.5 lb
  • Battery Weight:        2.9 lb
  • Payload weight:       5 lb internal
  • Gross Weight:          19 lb (Including external payload)

Features

  • Pneumatic main brakes
  • Removable boom tail
  • Foam wing construction
  • Remote control "bomb-bay" style payload release.  Bay door removable for installation of external antenna
  • Composite carbon sandwich panels for fuselage, carbon tailboom

Performance

  • Takeoff distance at full gross weight: <120 ft
  • Stall speed at full gross weight:    34 ft/sec
  • Max rate of climb at full gross weight:  7.3 ft/sec
Team Info: 

The OSU Black design team was led by a Chief Engineer, and divided into three primary groups: Aerodynamics/Stability and Control, Propulsion, and Structures.

Chief Engineer: Kevin Frye

Aerodynamics / Stability and Control:

  • Miranda Kovach (Lead)
  • Rory Murfin
  • Scott Thomason

Propulsion:

  • Aaron Thiessen
  • Amit Desai
  • Gerond George

Structures:

  • Steven Bogadi (Lead)
  • Kimber Caywood
  • Sofiri Hart
  • Richard Maxwell
  • Cody White
  • Amber Woods

Pilot: Dan Bierly

Spotter: Ronnie Lawhon

Faculty Advisor: Dr. Andrew S. Arena, Jr.

Assistant: Joe Conner

*(The above team roster does not include all people involved in the project)

Contest Summary: 

Teams were required to select two missions to fly at the contest, and the flight score from each was added together to achieve the overall flight score.  The three missions were:

  • Missile decoy:  A 5 lb block payload was carried internally, and a large external cylindrical payload was also carried.  The external payload was a 6 in diameter, 3 in tall enclosed PVC pipe that had to stand off a minimum of 3in from the fuselage.  The difficulty factor was highest for this mission.
  • Sensor deployment:  The 6in x 6in x 12in 5 lb internal payload had to be flown twice around the course, and dropped on the runway after coming to a complete stop.  The aircraft then had to take off and fly another two laps of the course.  All this had to be done remotely.  This mission had the next highest difficulty factor.
  • Communications repeater:  The aircraft had to fly 4 laps of the course with the internal payload and then land.  The airplane also had to perform 3 360 deg turns for each lap instead of one.  This mission had the lowest difficulty factor.

The mission score also depended on a timed task in which the aircraft which was initially stored in a 4'x2'x1' box, had to be assembled as quickly as possible.

Flight score was calculated as follows, and summed for two missions:

Difficulty Factor
Mission Flight Time + Aircraft Assembly Time

RAC was a "Rated Aircraft Cost" which penalized many aspects of the design.  It included penalties for design parameters such as; aircraft empty weight, engine power, wing area, etc.  A link to the complete rules may be found below.

Overall score was calculated by summing the two best flight scores, multiplying by written report score, and dividing by the RAC.

Some of the more challenging constraints on the designs included:

  • 120 ft short field takeoff distance
  • Brushed electric motor using NiCd batteries
  • High drag due to external payload of mission 1
  • Reliable remote control release of payload in mission two.  The mission required a well designed release system, as well as brakes, in order to drop the payload in the prescribed area.
  • Speed assembly of the aircraft.
  • Aircraft must be lifted at the wing tips at full gross weight

Complete Rules

Official Contest Summary

Results Summary: 
  • Report Score:     91.6
  • Flight Score:       0.89  (OSU Black chose missions 1 and 2 for the higher scoring potential.
  • Assembly time:   24 seconds
  • RAC:                    9.86
  • Total Score:        8228.28
  • Overall Place:     5th
 
Sponsors: 

The following sponsors contributed to the project.  The OSU Black team greatly appreciates their support, and considers them members of our team.  Without their support, the project would not have been possible.

Aero Services, Inc.
Chaney
Ditch Witch
El Chico
Industrial Rubber
Mercruiser
NASA Oklahoma Space Grant Consortium
OGE
Peascock
OSU Student Government Assoc.
Sally McGreevy
Sullivan
Westex
Wilcox
Whitehead

Category: 
Design, Build, Fly