Narrative:

Pushed back and called ATC for taxi [who then] cleared us to runway 5R for departure. Airbus just landing 5R. Taxied to 5R; [another] airbus landed on 23L. [The second airbus] cleared the runway and we were given take off clearance 5R; turn right to 070; climb 6000 ft. We had a deferred left thrust reverser so taking the runway I again briefed an aborted takeoff with one thrust reverser. As we got to V1 and then rotate I pitched up to the flight director; called for the gear up; and heading 070. Suddenly my airspeed started to degrade so I started to pitch down. We [then] received a windshear warning with the red eyebrow arrows [so] I started to pitch up to the bars and it went away. I thought it was a malfunction since we had no warning. The first officer called out airspeed and I did not call out for max power. The first officer noticed 25 knots of tail wind; we got to about 700 feet before we saw positive performance.suddenly having a windshear with no warning [early in the morning] can certainly bring about confusion. I believe if the two other aircraft could have provided a clue to the tower to pass on a degraded performance on landing we would have [taken a] delay and held off the runway till we got more information. As it was we were taking off with calm wind and no thunderstorms anywhere near the airport [so] we figured a normal takeoff but once again we found that normal is just a setting on a washing machine. As far as preventing this event we should have called max power and as it [happened] with no clues to what is going happen next was the big problem. We tried to stay SOP but this got thrown in and caused confusion.

Related reports:

Google
 

Original NASA ASRS Text

Title: CRJ-900 Captain reported encountering windshear on takeoff from TYS with no windshear warning provided.

Narrative: Pushed back and called ATC for taxi [who then] cleared us to runway 5R for departure. Airbus just landing 5R. Taxied to 5R; [another] Airbus landed on 23L. [The second Airbus] cleared the runway and we were given take off clearance 5R; turn right to 070; climb 6000 ft. We had a deferred left thrust reverser so taking the runway I again briefed an aborted takeoff with one thrust reverser. As we got to V1 and then rotate I pitched up to the flight director; called for the gear up; and heading 070. Suddenly my airspeed started to degrade so I started to pitch down. We [then] received a windshear warning with the red eyebrow arrows [so] I started to pitch up to the bars and it went away. I thought it was a malfunction since we had no warning. The first officer called out airspeed and I did not call out for max power. The first officer noticed 25 knots of tail wind; we got to about 700 feet before we saw positive performance.Suddenly having a windshear with no warning [early in the morning] can certainly bring about confusion. I believe if the two other aircraft could have provided a clue to the tower to pass on a degraded performance on landing we would have [taken a] delay and held off the runway till we got more information. As it was we were taking off with calm wind and no thunderstorms anywhere near the airport [so] we figured a normal takeoff but once again we found that normal is just a setting on a washing machine. As far as preventing this event we should have called max power and as it [happened] with no clues to what is going happen next was the big problem. We tried to stay SOP but this got thrown in and caused confusion.

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.