What is the ground duty cycle limit for the 1st and 2nd engine starter?

The ground duty cycle limit for the 1st and 2nd engine starter on the ERJ 170/175 series is defined as 90 seconds of operation followed by a 10-second rest period. This specification is crucial for maintaining the starter's integrity and preventing overheating, as excessive continuous use can lead to damage. By adhering to this limit, pilots can ensure that the starter operates within its design specifications, promoting reliability during engine start procedures.

The choice of 90 seconds on followed by 10 seconds off is particularly important in scenarios where multiple engine starts might be required in quick succession, allowing brief intervals for the starter to cool down. Proper understanding of these limits enhances operational safety and efficiency.

Other options, with longer operating times or different rest periods, do not align with the manufacturer's specific guidance, which is why they are not applicable in this context. Ensuring adherence to the correct starter duty cycle is vital for the longevity of the system and the overall performance of the aircraft's engines.