ASW-22DB (Eta Biter) Evolution
•
4 likes•8,427 views
The document summarizes the evolution of the ASW22DB glider through four phases from 1998 to 2003. Phase I involved building the ASW22BL with a smaller horizontal tail. Phase II modified the wing airfoil. Phase III included a new vertical stabilizer and retractable tail wheel. Phase IV added a new outboard airfoil profile, increased the span to 28m, and improved internal airflow. Performance gains anticipated included up to 11% at high speeds and improved climb. Flight tests verified the theoretical calculations and aerodynamic modifications. The completed glider met expectations by winning national competitions.
Recommended
More Related Content
What's hot
What's hot (20)
Viewers also liked
Viewers also liked (12)
Similar to ASW-22DB (Eta Biter) Evolution
Similar to ASW-22DB (Eta Biter) Evolution (20)
More from Glider Pilot
More from Glider Pilot (18)
Recently uploaded
Recently uploaded (20)
ASW-22DB (Eta Biter) Evolution
- 1. ASW22DB (ETA BITER) Evolution Feb98 to Jun03
- 2. Project Phases • Phase I- Build ASW22BL with 30% Less Horizontal Tail Area • Phase II- Modify HQ17 Airfoil Inboard Wing • Phase III- New Vertical Stabilizer and Retractable tail wheel • Phase IV- New Outboard Airfoil Profile, Span Increase to 28m, Internal Air Flow Improvement
- 3. Anticipated Performance Gains From Project Phases • 9% Performance Gain at Best L/D • 11% Performance Gain at High Speeds, (160km/hr) • Improved Climb Performance From Reduced Span Loading • Equal flying qualities with 28m Span by Maintaining Vertical Tail Volume Coeff. (V/S.b)
- 4. Phase I- Build ASW22BL With Smaller Horizontal Stabilizer • 2.6% Less profile drag relative to wing • Good stability/elevator authority on tow & low speed flight (Minimum pilot wt. 88kg)
- 5. Phase II- Modify HQ 17 Airfoil • Prof. Loek Boermans Designs Modification to HQ17 Airfoil Lower Surface for 7.5% Less Skin Friction Drag at High Speeds (6.0 percent relative to wing).
- 7. Flight Test Verify Theoretical Calculations Parasite Drag ASW22DB 0.9 0.8 flap -8.6deg, HQ17M,zz tape TE 80% , no blowing 0.7 Flap -8.6deg, HQ17, blow holes at 73% 0.6 0.5 Cl 0.4 0.3 0.2 0.1 0 0 0.001 0.002 0.003 0.004 0.005 0.006 0.007 Cd
- 8. Blowing Articulation • Blow Holes at 72% • Blowing Set as a Function of Flap Position • NACA Ducts Opened & Closed by Servos Mounted Over Plenum
- 9. Delft HQ17M Airfoil Design Was Implemented and Flight Tested
- 10. Phase III- New Vertical Stabilizer & Retract Tail Wheel • Reasons For Building -Drag reduction with modern profile -Maintain 22BL tail volume coefficient(V/S.b) with 28m span (add 30cm tail boom, 10cm span) -Center hinged rudder -Drag reduction with retract tail wheel • Benefits - 25% Less profile drag - 2.2% Less drag relative to wing - Better handling from new profile and center hinged rudder
- 15. Perspective
- 16. Phase IV- New Airfoil on Outboard Wing, Span to 28m • Reasons for Changes - Improve lift distribution to near elliptical - Less profile drag with Delft DU99-138 - Improve low speed, 1.8m more span - Strengthen wing for 850kg max weight • L. Boermans & M. Hulst designed new airfoil and winglet for outer wing panel • 2% Less profile drag at high speeds & 4% at low speeds relative to wing.
- 17. Skin Removal & Contouring
- 18. Skin Replacement & Aileron Construction
- 19. New Airfoil & Wing Contouring
- 25. Ship met All Expectations Winning 03 Open Class Nationals
- 26. Remaining Work • Build Lighter Weight Ailerons • Build and Test Delft Winglets per Boermans & Hulst Design • Obtain Performance Polar for Completed ASW22DB
- 27. ASW22BL, wt 1279, New VS, Retract Tailwheel, Exhaust in Turtle Deck,New Delft Airfoil to Sta 8.25, NACA Duct Driven by Servo, No Winglets, W/S 7.13lb/sq ft 700 flap -8.6deg, no blowing" 600 flap -6.5deg, blowing Measured factory polar for ASW22B corrected to BL 500 rate of sink, ft/sec flap -4.4deg, blowing 400 Flap 0deg, blowing 300 flap- 2.2deg, blowing 200 100 0 0 20 40 60 80 100 120 140 airspeed, kts
- 28. Comparisons ASW22BL Nimbus 4 ASW22DB ETA Span 26.4m 26.4m 28.0m 30.9m Wing Area 16.7m^2 17.8m^2 17.0m^2 18.6m^2 Aspect Ratio 41.8 39.2 46.1 51.3 MTOW 750kg 750kg 750 (850)kg 850kg Wing Loading 45.0kg/m^2 42.1kg/m^2 44.1kg/m^2 44.8kg/m^2 Span Loading 28.4kg/m 28.4kg/m 26.7kg/m 27.5kg/m V/sb .05 .04 .05 ?
- 29. Design Team