Using the AIP for instrument approaches?? Is it correct
 

Is it safe and correct to use the AIP for instrument approaches?? For instance if you didnt want to buy an aerad.

If the AIP was the one published by a national aviation authority, then yes.
You must bear in mind that companies like AERAD and Jeppesen copy the AIP to design their charts, however whereas the AIP is produced under a tried and tested safety audit procedure, there are NO facilities to regulate AERAD/Jepp to ensure the info they publish is correct, so you may be relying on incorrect info.

the AIP charts and jeppesen charts in my country presents different information sometimes,and consistently different height info such as the TDZ elevation and MDA..in terms of 10-20 ft..just a point. :)

That is most strange. Do not know about Singapore, but many countries only publish OCH/A in their AIPs derived from obstacle survey and procedure design. I just checked AIP U.K. and yes is shows OCH of about 160 ft for CAT I ILS. It is no nosense, that is your obstacle floor. We all know that minima for CAT I ILS are no less than 200 feet. So no problem. Only that the pilot - operator must take data from AIP and create minima out of them observing all applicable regulations normally from Annex 6 / JAR OPS / applicable FAR part. One way to do it is to buy AREAD / Jepp an use this. Of course, should you make an error due to wrongly printed book it is entirely your fault.

machlimiter99: Many would argue that is it only perfect way to do it. However some commercial publications are more user friendly and make very sure you well understand the difference between OCA/H vs. DA/H & MDA/H as described above.


Fd
(the un-real)