diff --git a/user_manual/images/contact_thunderbird-Symbol_Gear.jpg b/user_manual/images/contact_thunderbird-Symbol_Gear.jpg deleted file mode 100755 index d9f60413c..000000000 Binary files a/user_manual/images/contact_thunderbird-Symbol_Gear.jpg and /dev/null differ diff --git a/user_manual/images/contact_thunderbird-Symbol_Impeller.jpg b/user_manual/images/contact_thunderbird-Symbol_Impeller.jpg deleted file mode 100755 index a3e7fe53b..000000000 Binary files a/user_manual/images/contact_thunderbird-Symbol_Impeller.jpg and /dev/null differ diff --git a/user_manual/images/contact_thunderbird-URL_config.jpg b/user_manual/images/contact_thunderbird-URL_config.jpg deleted file mode 100755 index 9ab48faaf..000000000 Binary files a/user_manual/images/contact_thunderbird-URL_config.jpg and /dev/null differ