Narrative:

We arrived at the plane as the previous crew was deplaning. The previous crew reported the APU was deferred due to the APU fire bottle discharging on a landing. The previous crew reported unsuccessful attempts to get conditioned air hooked up to the plane by the ground crew. We took over the airplane and started the normal flight prep activities. We were able to finally get conditioned air to the airplane from the ground crew. This took much prodding over the operations frequency. Prior to boarding I got the current ATIS and clearance. I don't remember the full ATIS but the outside temperature was reported at 41 degrees C. We boarded the plane and at the time the cabin temp was right at 30 degrees C. We had 44 passengers total. We used a bottle start to get the #2 engine started. Through this process we kept the conditioned air hooked to the airplane to provide some level of comfort to the passengers. Prior to pushback all air sources were disconnected and we completed a normal pushback. We asked ground control for a cross bleed start as soon as possible. Cabin temperature had started to rise. We completed a cross bleed start; checklists; and continued our taxi. In an attempt to keep airflow in the cabin we taxied with a slightly higher thrust setting to keep pressure and airflow to the packs in an attempt to keep the cabin temperature under control. This required more braking then normal. I completed the before takeoff check and about the time I was checking for the takeoff configuration ok message I noticed the brake temperatures and we had a brake overheat warning message. The left outboard was at 14 and the right outboard was at 11. Both had the red boxes. The inboard brakes on both mains were around 6 or 7 with the white boxes. I alerted the captain and we told tower our intention not to takeoff. The captain called maintenance and we were advised to let the brakes cool. We arranged for a holding spot to allow the brakes to cool. As we sat in the holding spot we kept the flight attendant and passengers updated with the situation. In an effort to keep the airplane cool we ran the engines slightly higher then normal to keep the airflow in the cabin which lead to going below our min for takeoff fuel. The captain called dispatch on 2 occasions to have the fuel numbers adjusted. The cabin temperature was up around 38 degrees by this time despite our efforts to keep the interior cool. Throughout this time the flight attendant did a water service and communicated the some of the passengers were getting uncomfortable with the temperature. The brakes finally cooled down to around 4 which the indications should have turned green. The inboard brake temperatures were green while the outboard remained with a red box although the temperature was around a 5. We decide to taxi to the runway for another departure attempt. We thought that the additional airflow over the brakes during the final taxi would aid the cooling. We again completed all the required checklists. Prior to takeoff we still had the brake overheat message even though the indications were normal except for the red boxes on the outboard temperatures. We canceled the takeoff clearance. We taxied down the runway and pulled back onto a taxiway. During the taxi the captain remarked that it felt like a brake pad was grabbing. Once clear of the runway the flight attendant communicated that some passengers were ready to return to the gate due to the cabin temperature. We communicated to operations that we needed a gate as soon as possible. We also stated we needed air and power. This was approximately 10-15 minutes before we actually got parked at the gate. The captain at some point also communicated to have EMS on standby to assist any passengers that might need any help. We arrived short of the gate and there was no ground personal in sight; after numerous attempts over the operations frequency the ground personal showed up to park us. There was still no gate agent as well. We parked and waited for a gate agent. The ground crew could not hook up conditioned air until the jetbridge was moved. One of the ground crew came up in the cockpit and informed us that we had a flat tire and that there was no ground power at the gate. The captain went up the jetbridge in search of a gate agent. I remained in the cockpit to guard the brakes since we still had both engines running to keep airflow going. An agent showed up in a rush in a car and moved the jetbridge. I shut down the #1 engine so the crew could hook up the air and the passengers were deplaned. The captain returned and we left the #2 engine running to provide power. At some point in this process we finally got a gpu and shut the engine down. Total time elapsed from calling for a gate to deplaning was about 15 minutes maybe more. The emt's showed up and treated a few passengers inside the gate. I am unsure on those details as I did not go into the gate area at the time. Total block for the taxi and return to the gate was 1:22.first and foremost I think the company needs to pull an aircraft from passenger service with a deferred APU in cases of extreme heat which lead to extreme discomfort to both the passengers and crew. The high temps in the cockpit made for a distraction as well as a danger to the crew.

Related reports:

Google
 

Original NASA ASRS Text

Title: CRJ50 flight crew experiences high brake temperatures prior to takeoff after attempting to cool the cabin during taxi with higher than normal thrust settings. Flight returns to the gate due to high cabin temperatures and brake temperatures that remain in the red. Very high ambient temperatures were responsible and a flat tire was noted upon gate return.

Narrative: We arrived at the plane as the previous crew was deplaning. The previous crew reported the APU was deferred due to the APU fire bottle discharging on a landing. The previous crew reported unsuccessful attempts to get conditioned air hooked up to the plane by the ground crew. We took over the airplane and started the normal flight prep activities. We were able to finally get conditioned air to the airplane from the ground crew. This took much prodding over the Operations frequency. Prior to boarding I got the current ATIS and clearance. I don't remember the full ATIS but the outside temperature was reported at 41 degrees C. We boarded the plane and at the time the cabin temp was right at 30 degrees C. We had 44 passengers total. We used a bottle start to get the #2 engine started. Through this process we kept the conditioned air hooked to the airplane to provide some level of comfort to the passengers. Prior to pushback all air sources were disconnected and we completed a normal pushback. We asked Ground Control for a cross bleed start as soon as possible. Cabin temperature had started to rise. We completed a cross bleed start; checklists; and continued our taxi. In an attempt to keep airflow in the cabin we taxied with a slightly higher thrust setting to keep pressure and airflow to the packs in an attempt to keep the cabin temperature under control. This required more braking then normal. I completed the before takeoff check and about the time I was checking for the takeoff configuration OK message I noticed the brake temperatures and we had a brake overheat warning message. The left outboard was at 14 and the right outboard was at 11. Both had the red boxes. The inboard brakes on both mains were around 6 or 7 with the white boxes. I alerted the Captain and we told Tower our intention not to takeoff. The Captain called Maintenance and we were advised to let the brakes cool. We arranged for a holding spot to allow the brakes to cool. As we sat in the holding spot we kept the Flight Attendant and passengers updated with the situation. In an effort to keep the airplane cool we ran the engines slightly higher then normal to keep the airflow in the cabin which lead to going below our min for takeoff fuel. The Captain called Dispatch on 2 occasions to have the fuel numbers adjusted. The cabin temperature was up around 38 degrees by this time despite our efforts to keep the interior cool. Throughout this time the Flight Attendant did a water service and communicated the some of the passengers were getting uncomfortable with the temperature. The brakes finally cooled down to around 4 which the indications should have turned green. The inboard brake temperatures were green while the outboard remained with a red box although the temperature was around a 5. We decide to taxi to the runway for another departure attempt. We thought that the additional airflow over the brakes during the final taxi would aid the cooling. We again completed all the required checklists. Prior to takeoff we still had the brake overheat message even though the indications were normal except for the red boxes on the outboard temperatures. We canceled the takeoff clearance. We taxied down the runway and pulled back onto a taxiway. During the taxi the Captain remarked that it felt like a brake pad was grabbing. Once clear of the runway the Flight Attendant communicated that some passengers were ready to return to the gate due to the cabin temperature. We communicated to Operations that we needed a gate ASAP. We also stated we needed air and power. This was approximately 10-15 minutes before we actually got parked at the gate. The Captain at some point also communicated to have EMS on standby to assist any passengers that might need any help. We arrived short of the gate and there was no ground personal in sight; after numerous attempts over the Operations frequency the ground personal showed up to park us. There was still no gate agent as well. We parked and waited for a gate agent. The ground crew could not hook up conditioned air until the jetbridge was moved. One of the ground crew came up in the cockpit and informed us that we had a flat tire and that there was no ground power at the gate. The Captain went up the jetbridge in search of a gate agent. I remained in the cockpit to guard the brakes since we still had both engines running to keep airflow going. An agent showed up in a rush in a car and moved the jetbridge. I shut down the #1 engine so the crew could hook up the air and the passengers were deplaned. The Captain returned and we left the #2 engine running to provide power. At some point in this process we finally got a GPU and shut the engine down. Total time elapsed from calling for a gate to deplaning was about 15 minutes maybe more. The EMT's showed up and treated a few passengers inside the gate. I am unsure on those details as I did not go into the gate area at the time. Total block for the taxi and return to the gate was 1:22.First and foremost I think the company needs to pull an aircraft from passenger service with a deferred APU in cases of extreme heat which lead to extreme discomfort to both the passengers and crew. The high temps in the cockpit made for a distraction as well as a danger to the crew.

Data retrieved from NASA's ASRS site as of April 2012 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.