Narrative:

On climb out through FL180 we received a brakes hot ECAM. We decided to lower the gear to decrease the temperature below the 300 degrees C threshold. We asked ATC if we could stop the climb at FL230 and accelerate to 250 KTS for a few mins. I was hand-flying at the time and bled off the speed in the climb to FL230. Reaching FL230 we were still faster than the maximum extension speed of 250 KTS. As we leveled off at FL230 I engaged the autoplt to minimize workload. At that time we were in 'altitude;' not altitude. Once we slowed to 250 KTS; the captain asked if I was ready and I said yes. When the gear extended the autoplt had trouble finalizing the leveloff and began to climb approximately 300 ft above FL230. I observed the climb but chose to leave the autoplt engaged. As the autoplt corrected back toward FL230 I made the mistake of diverting my attention toward the gear extension. A few moments later the airplane descended through FL230 and the captain said 'watch your altitude' and then proceeded to disconnect the autoplt and hand-fly it back to altitude. Once stabilized at FL230; I elected to hand-fly during the gear retraction which was significantly smoother and easier than using the autoplt. On a side note; when the captain disconnected the autoplt; the autoplt off alarm led me to grab my sidestick unsure of whether the captain disconnected the autoplt or not. I did not hear him say he had the airplane; but it's possible he did and I didn't hear it with the added noise. For about 5 seconds we were making conflicting stick inputs at which time I asked him if he too was on the stick. When he replied that he was; I slowly released my stick inputs. We never received a dual input notification; but I presume it was too short of a time period to get the notification. Leveling FL230; the captain xferred control back to me.

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Original NASA ASRS Text

Title: A319 FLT CREW AT FL230 HAS TROUBLE MAINTAINING ALT DURING GEAR EXTENSION AND REACTION TO COOL HOT BRAKES.

Narrative: ON CLBOUT THROUGH FL180 WE RECEIVED A BRAKES HOT ECAM. WE DECIDED TO LOWER THE GEAR TO DECREASE THE TEMP BELOW THE 300 DEGS C THRESHOLD. WE ASKED ATC IF WE COULD STOP THE CLB AT FL230 AND ACCELERATE TO 250 KTS FOR A FEW MINS. I WAS HAND-FLYING AT THE TIME AND BLED OFF THE SPD IN THE CLB TO FL230. REACHING FL230 WE WERE STILL FASTER THAN THE MAX EXTENSION SPD OF 250 KTS. AS WE LEVELED OFF AT FL230 I ENGAGED THE AUTOPLT TO MINIMIZE WORKLOAD. AT THAT TIME WE WERE IN 'ALT;' NOT ALT. ONCE WE SLOWED TO 250 KTS; THE CAPT ASKED IF I WAS READY AND I SAID YES. WHEN THE GEAR EXTENDED THE AUTOPLT HAD TROUBLE FINALIZING THE LEVELOFF AND BEGAN TO CLB APPROX 300 FT ABOVE FL230. I OBSERVED THE CLB BUT CHOSE TO LEAVE THE AUTOPLT ENGAGED. AS THE AUTOPLT CORRECTED BACK TOWARD FL230 I MADE THE MISTAKE OF DIVERTING MY ATTN TOWARD THE GEAR EXTENSION. A FEW MOMENTS LATER THE AIRPLANE DSNDED THROUGH FL230 AND THE CAPT SAID 'WATCH YOUR ALT' AND THEN PROCEEDED TO DISCONNECT THE AUTOPLT AND HAND-FLY IT BACK TO ALT. ONCE STABILIZED AT FL230; I ELECTED TO HAND-FLY DURING THE GEAR RETRACTION WHICH WAS SIGNIFICANTLY SMOOTHER AND EASIER THAN USING THE AUTOPLT. ON A SIDE NOTE; WHEN THE CAPT DISCONNECTED THE AUTOPLT; THE AUTOPLT OFF ALARM LED ME TO GRAB MY SIDESTICK UNSURE OF WHETHER THE CAPT DISCONNECTED THE AUTOPLT OR NOT. I DID NOT HEAR HIM SAY HE HAD THE AIRPLANE; BUT IT'S POSSIBLE HE DID AND I DIDN'T HEAR IT WITH THE ADDED NOISE. FOR ABOUT 5 SECONDS WE WERE MAKING CONFLICTING STICK INPUTS AT WHICH TIME I ASKED HIM IF HE TOO WAS ON THE STICK. WHEN HE REPLIED THAT HE WAS; I SLOWLY RELEASED MY STICK INPUTS. WE NEVER RECEIVED A DUAL INPUT NOTIFICATION; BUT I PRESUME IT WAS TOO SHORT OF A TIME PERIOD TO GET THE NOTIFICATION. LEVELING FL230; THE CAPT XFERRED CTL BACK TO ME.

Data retrieved from NASA's ASRS site as of January 2009 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.