Date: 201907
Local time of day: 0601-1200
Location: CHO.Airport, VA
Flight conditions: VMC
Weather elements / visibility: Thunderstorm
Light: Daylight
Aircraft: EMB ERJ 145 ER/LR
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Taxi
ATC / advisory: Ground CHO
Aircraft component: APU
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: First Officer; Pilot Flying
Reporter qualification: Flight Crew Multiengine; Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP)
Human factors: Communication Breakdown; Situational Awareness; Time Pressure; Training / Qualification
Second reporter function: Captain; Pilot Flying
Anomaly: Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy; Flight Deck / Cabin / Aircraft Event Other / Unknown
Detector: Person Flight Crew
When detected: Taxi
Result: Flight Crew Returned To Gate; General Flight Cancelled / Delayed; General Maintenance Action
Contributing factors: Aircraft; Human Factors; Procedure; Staffing; Company Policy
Primary problem: Aircraft

Narrative: Left gate early; normal pushback. Cleared to spin Eng 2. Normal rotation; Fuel Flow. Just prior to light-off APU spiked to 700C+ and initiated auto-shutdown. As a result #2 start rapidly rose to beyond 700C ITT (Interstage Turbine Temperature) (Hot Start) and would have continued so abort procedure initiated.Ran QRH to Restart considered. Ramp crew requested to disconnected to enable them to marshal in another aircraft. We agreed with the provision that they stay in visual and radio contact with us. They assured us they would be listening and would be just next gate over.Called Maintenance Control due to nature of being at gate. During this time battery voltage was noted as dropping steadily (21.4v). Too low for APU start. Initiated power-saving procedures (shut down Avionics).During this process I attempted to communicate with Rampers to get a tow back into gate with zero contact. After 5 mins of failed attempts I called Operations which took several times. Finally made contact with Operations and communicated that we were without APU or any power and on battery 'only'; and; the batteries were draining fast and request immediate tow back into the gate due to the rapidly rising cabin temps. More than 15 minutes lapsed from time of contact with Operations to time that anyone on the ramp seemed to notice we were in need of attention. They mustered three Rampers to marshal us in but not aware we had no power.(Note: Phone calls were also placed to Dispatch again to inform them we still had negative contact with Operations to please call. Additionally; the Tower was called to also hail Operations on the phone to get us a tow-in. Apparently Dispatch had to call the airport police to get them to find Operations personnel.)After much hand gesturing they approached the aircraft and had no idea we couldn't taxi in and did not have power. Both cockpit DV (Direct Vision) windows had to be opened in the meantime due to the elevated 42C temperatures! Through the side window we communicated we needed a tow in at which time we were told by the Ramp Supervisor that they are not 'Tow-in' certified! He then proceeded to explain he had to call [Operations] and [Company] to see what they could do to help. At this point the Captain gave the Ramper two options (a) tow us back into the gate (b) deplane in place if nothing is done within the next 5 mins due to the rising heat in the cabin. The Captain initiated contact with the Flight Attendant to inform her of the current situation and to also open the service door for airflow if necessary and to serve water and to inform the passengers of the pending situation.5 more minutes and the Ramp Supervisor approached the Captain window to tell us we would deplane in place. Ground was contacted and coordinated with approval. The police department was on scene to assist with marshaling the passengers to the terminal. Successful deplane occurred with no issues.Once deplane completed it was then decided by the Ramp Supervisor to have us towed back into the gate after much debate. All this after telling us they could not for more than 30 minutes prior! Upon reaching the gate the ramp closed due to thunderstorms in the vicinity so we exited the aircraft.Spoke directly to several of the Rampers and the Supervisor and told them this was a serious issue and that not one ramper in a course of 15 mins even looked our way or even seemed to really care that we had a major issue on our hands. I also explained it posed a safety issue that we never released them from our pushback. Several of the Rampers said they did not have the proper information or training to deal with our sort of situations.


Second narrative: [Report narrative contained no additional information.]


Synopsis: EMB-145 flight crew reported that an APU auto-shutdown caused an extended ground event; exacerbated by lack of communication and unqualified ground crew.