Grob 103 Twin Astir, N7813, Performance Summary

The data on this page are gathered from the factory published owners manual and are deemed to be correct.
However, it is the pilots sole responsibility to verify and fly the a/c within the limits of factory published information.
For 7813 document and equipment data, including SN10 information: Scroll to the bottom of the page.

For new users of the SN10, download and read the suggestions of the following document: Getting Started With The SN10
Weight and Balance
Empty Weight 958 lbs.
Maximum Weight 1435 lbs.
Maximum Useful Load 477 lbs.
Minimum front seat load for all flights* 154* lbs.
Maximum Front Seat Load 242 lbs.
Maximum Rear Seat Load 242 lbs.
Maximum Bagage Compartment Load 22 lbs.
Seat ballast must be installed if front seat load is less than 154 lbs.
Air Speeds
Maximum Speed calm air Vne 135 kts
Maximum Speed to Deploy Spoilers V 135 kts
Maneuvering Speed Va 92 kts
Maximum Aerotow Speed Vt 92 kts
Minimum recommended approach speed Vref 56 kts
Maximum crosswind component V 11 kts
Stall Speeds Without Dive Brakes With Divebrakes
Solo 36 kts 41 kts
Dual 41 kts 49 kts
Flying in rain raises stall speeds by 7 MPH. With wet wings increase take-off and approach speeds accordingly.
Speeds to Fly Solo Dual
Minimum Sink 40 kts 49 kts
Best L/D ~36/1 51 kts 60 kts

Glider N7813 Documents

Twin Astir Checklist
SN10 Quick Reference
N7813 Loading Graph
N7813 Weight and Balance

Glider Manuals

Twin Astir Flight Manual
Twin Astir Maintenance Manual
Twin II Repair Instructions (NOT specifically for Twin Astir)
2014 TDSC G39EU

Equipment Manuals

Becker 4201 Installation and Operation Manual
Winter STV-5 Variometer Installation Manual
SN-10 Users Manual
SN-10 USB Users Manual


ILEC Website
SN-10 Resources Page
SN-10 Utah Waypoints and Airspace file: FOR DEMONSTRATION PROGRAM USE ONLY

N7813 Misc Information

N7813 Wiring Diagram - March 2018
Becker 4201 Wiring Diagram
Becker 4201 Data Sheet
Becker 4201 Brochure