It depends on your exact question, but probably not. Even if Aescrypt happens to use cryptography and happens to be used for security purposes, that doesn't automatically make it on-topic here.
Generally speaking, questions about tools are off-topic, unless they are tools specifically used by security professionals (or by people acting as such). For example, a question about how to use Nessus or Metasploit is likely to be on-topic, whereas a question about how to use SSH or Truecrypt is likely to be off-topic. A question asking how to set up a firewall with a given tool would be off-topic, but a question asking what firewall rules would implement a desired security policy would be on-topic.
“What is the format of an Aescrypt key file?” would be off-topic. It would be on-topic on Super User.
An example on-topic question would be “How does Aescrypt protect the confidentiality of the data if the hard disk is stolen?”. It's on-topic because it's about the security implications of how Aescrypt works.