EMB-175 Flight Crew reported on takeoff receiving numerous erroneous warning messages and radar altimeter readings.
Synopsis
EMB-175 Flight Crew reported on takeoff receiving numerous erroneous warning messages and radar altimeter readings.
Narrative
Date. Day VMC takeoff in ZZZ. On takeoff roll; EICAS advisory message Autoland 1 Not Avail and Appr 2 Not Avail posted. In addition; the CA (Captain) side Radar Altimeter was showing erroneous indications of being over 1;000 feet above the ground. The Captain (Pilot Flying) continued the takeoff; deciding these were not warranting a rejected takeoff. After rotation and gear selection up; we received a ground proximity caution saying 'Caution Too Low Terrain'. When the caution sounded; the Captain advanced the throttles to max and climbed steeper. Noticing the aircraft flight progress and being clear of terrain; the Captain reduced throttles back to the TOGA detent and continued the climb as normal. Throttles were in max for about 30 seconds or less. No engine parameters were observed to be exceeded. Departure continued normal on the assigned SID; and I as the PM (Pilot Monitoring); continued to configure the aircraft as normal; monitored the flights parameters; altitude; and terrain clearance; and conducted the after takeoff checklist.The autoland; approach and radar altimeter issues noted on the takeoff roll are not uncommon for the E-175. They are transitory and often clear after several seconds. We have these advisories during ramp and taxi operations nearly every day and they clear away with no degradation of operational safety. We had the advisories appear and clear away on taxi out; but during the before takeoff checklist; all messages had cleared when I checked the EICAS. Being a day VMC flight; the captain decided those messages would not require a rejection of takeoff. The GPWS caution came as a surprise to both of us; but after the Captain (PF) selected max thrust and climbed steeper we both assessed the departure was in a safe environment. I believe the caution was erroneous and was due to false radar altimeter information.I'm not sure what caused this error. Having had all these messages occur on previous flights gave both the Captain and I had a sense that it would not affect the flight in such a manner. In addition; Runway XXL is listed as having AMOC (Alternate Method of Compliance) protection from the 5G NOTAMs. Lessons learned are to be very aware when the radar altimeter is reading erroneously; and if I were to be the PF; pitch a little higher for a GPWS caution even if suspected to be a false caution.
Second reporter narrative
Date. Day VMC takeoff in ZZZ. On takeoff roll; EICAS (Engine Indicating and Crew Alerting System) advisory message Autoland 1 Not Avail and Appr 2 Not Avail posted. In addition I noticed the CA (Captain) side Radar Altimeter was showing erroneous indications of being over 1;000 feet above the ground. I continued the takeoff; deciding these were not warranting a rejected takeoff. After rotation and gear selection up; we received a ground proximity caution saying 'Too Low Terrain'. When the caution sounded; I advanced the throttles to max and climbed steeper. Noticing the aircraft flight progress and being clear of terrain; I reduced throttles back to the TOGA detent and continued the climb as normal. Throttles were in max for about 30 seconds or less. No engine parameters were observed to be exceeded. Departure continued normal. The autoland; approach and radar altimeter issues noted on the takeoff roll are not uncommon for the E175. They are transitory and often clear after several seconds. We have these advisories during ramp operations nearly every day and they clear away with no degradation of operational safety. We had the advisories appear and clear away on taxi out; but during the before start checklist; all messages had cleared. Being a day VMC flight I decided they would not require a rejection of takeoff. The GPWS caution came as a surprise but after selecting max thrust and climbing steeper I noticed the departure was in a safe environment. I believe the caution was erroneous and was due to false radar altimeter information.I'm not sure what caused this to occur. Having had all these messages occur on previous flights gave me a sense that it would not affect the flight in such a manner. Lessons learned are to be very aware when the radar altimeter is reading erroneously and to pitch a little higher for a GPWS caution; even if suspected to be a false caution.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.