A300 first officer reported encountering severe to extreme turbulence at FL340.

Attributes
ACN	1717683
Time
Date	202001
Place
Locale Reference	ZZZ.ARTCC
State Reference	US
Environment
Flight Conditions	IMC
Aircraft 1
Make Model Name	A300
Operating Under FAR Part	Part 121
Flight Phase	Cruise
Flight Plan	IFR
Component
Aircraft Component	Weather Radar
Person 1
Function	First Officer Pilot Not Flying
Qualification	Flight Crew Instrument Flight Crew Multiengine Flight Crew Air Transport Pilot (ATP)
Events
Anomaly	Aircraft Equipment Problem Less Severe Deviation - Procedural Published Material / Policy Inflight Event / Encounter Weather / Turbulence Inflight Event / Encounter Loss Of Aircraft Control

Narrative:

At FL340 aircraft encountered severe to extreme turbulence causing uncontrollable pitch; roll; and yaw. Captain disconnected the autopilot and regained control of the aircraft.aircraft radar was not displaying convective activity; causing convective area penetration.suggestions: improved aircraft radar; onboard nexrad weather for strategic information; ATC communication of their nexrad along with dispatch nexrad information.

Original NASA ASRS Text

Title: A300 First Officer reported encountering severe to extreme turbulence at FL340.

Narrative: At FL340 aircraft encountered severe to extreme turbulence causing uncontrollable pitch; roll; and yaw. Captain disconnected the autopilot and regained control of the aircraft.Aircraft radar was not displaying convective activity; causing convective area penetration.Suggestions: Improved aircraft radar; onboard NEXRAD weather for strategic information; ATC communication of their NEXRAD along with dispatch NEXRAD information.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.