ao-sky-flash: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/ao-sky-flash - from package: altos

You may install the required package with command apt-get install {package}

Error in other languages:
ao-sky-flash: bevel nie gevind nie
ao-sky-flash: comandă negăsită
ao-sky-flash: comando não encontrado
ao-sky-flash: commande introuvable
ao-sky-flash: command not found
ao-sky-flash: käsku ei ole
ao-sky-flash: không tìm thấy lệnh
ao-sky-flash: komanda nerasta
ao-sky-flash: Kommando nicht gefunden.
ao-sky-flash: kommandot finns inte
ao-sky-flash: komut yok
ao-sky-flash: nie znaleziono polecenia
ao-sky-flash: níor aimsíodh an t-ordú
ao-sky-flash: no se encontró la orden
ao-sky-flash: no s'ha trobat l'ordre
ao-sky-flash: opdracht niet gevonden
ao-sky-flash: parancs nem található
ao-sky-flash: perintah tidak ditemukan
ao-sky-flash: príkaz nenájdený
ao-sky-flash: příkaz nenalezen
ao-sky-flash: команда не найдена
ao-sky-flash: командата не е открита
ao-sky-flash: 命令找不到
ao-sky-flash: コマンドが見つかりません