I came upon some texts where in able to is used where instead also either to be able to or in order to could have been used. In able to doesn't sound quite right to me. I also didn't hear it anywhere before. At first i thought in able to was just a mistake but now i'm not so sure anymore. I googled it but but i didn't find any real arguments against it.
Some Examples:
In addition to that, we had to wait a long time in able to query
the next request (sometimes over 30 minutes).
Previously, it has been suggested that S. aureus in able to survive without replication in neutrophils, > but ultimately cause lysis (Voyich et al., 2005; Kobayashi et al., 2010).
Questioned about whether electronic surveillance of social networks by
agencies including the NSA and GCHQ is damaging for democracy, Gadde
pointed to Twitter's decision to sue the FBI and US Department of
Justice in October 2014 in able to publish more details about
government requests for user information.
Source: theguardian.com
My question is wheter in able to is a existing term or not.
Best Answer
Probably, but you're right - it sounds clunky.
I'd go with "in order to", "so as to" .. or just "to" when possible.