Narrative:

Was on climb out of ZZZ with an ATC instruction to keep visual separation with [carrier] flight; also on departure; in front of us about 3 miles. We were climbing on the RNAV departure at about 5;500 with clearance to 9;000 feet. Our configuration was LNAV; VNAV/flch. Clouds were scattered about 6;000 feet. The [carrier] flight in front went in to IMC; therefore us losing visual separation. The captain; pilot monitoring; made a call to ATC saying we had visual with the other aircraft. ATC then says 'then level off your altitude' with no call sign or flight number. At the time I was hand flying; so I simply pushed the nose over to level off and stay VMC. Since we were still configured in flch/VNAV; the aircraft continued to accelerate to about 280 KIAS; therefore breaking the 250 KIAS below 10;000 feet. I caught it quickly and reduced power; slowing back down to 250 knots and staying level in VMC. Shortly after we were given a clearance to climb to 7;000. The autopilot was then engaged; and continued to 7;000 with no further deviations. If we hadn't been left with a visual separation clearance for so long; this would have never happened. With the auto throttles engage and in flch climb mode; I realize the throttles will maintain takeoff thrust; they were overridden to fix the problem; but could have been caught a few seconds earlier. In the future; I will keep a better eye on the airspeed in other unusual circumstances like this one.

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Original NASA ASRS Text

Title: An ERJ flight crew reported that; due to cloud conditions; they were unable to maintain visual reference from preceding traffic. After advising ATC of the situation they were told to level off immediately; resulting in a momentary speed excursion to 280 knots below 10;000 feet. A correction was accomplished and the flight continued uneventfully.

Narrative: Was on climb out of ZZZ with an ATC instruction to keep visual separation with [carrier] flight; also on departure; in front of us about 3 miles. We were climbing on the RNAV departure at about 5;500 with clearance to 9;000 feet. Our configuration was LNAV; VNAV/FLCH. Clouds were scattered about 6;000 feet. The [carrier] flight in front went in to IMC; therefore us losing visual separation. The captain; pilot monitoring; made a call to ATC saying we had visual with the other aircraft. ATC then says 'then level off your altitude' with no call sign or flight number. At the time I was hand flying; so I simply pushed the nose over to level off and stay VMC. Since we were still configured in FLCH/VNAV; the aircraft continued to accelerate to about 280 KIAS; therefore breaking the 250 KIAS below 10;000 feet. I caught it quickly and reduced power; slowing back down to 250 knots and staying level in VMC. Shortly after we were given a clearance to climb to 7;000. The autopilot was then engaged; and continued to 7;000 with no further deviations. If we hadn't been left with a visual separation clearance for so long; this would have never happened. With the auto throttles engage and in FLCH climb mode; I realize the throttles will maintain takeoff thrust; they were overridden to fix the problem; but could have been caught a few seconds earlier. In the future; I will keep a better eye on the airspeed in other unusual circumstances like this one.

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.