Change font type and size of all section and subsection headings

The font for normal text should be Times New Roman. But I want to change the section and subsection headings to Uppercase-Arial-12 Size.The MWE is shown below.

documentclass[letterpaper,11pt]{article}
\usepackage[left=1.25in,right=1.25in,top=1in,bottom=1in]{geometry}
\usepackage[english]{babel}
\usepackage{blindtext}
\usepackage{mathptmx}% Times Roman font
\title{My Title}
\date{}
\begin{document}
\maketitle
\Blinddocument
\end{document}

• You've tagged this with titlesec but you're not loading the package. See Change size of section, subsection, subsubsection, paragraph and subparagraph title for the general idea of how to do this. mathptmx is deprecated, better to replace it with newtxtext and newtxmath. If you need the exact fonts, use xelatex or lualatex. See How do I set the document body to be Times New Roman and Section headings to be Arial? – Alan Munn Aug 25 '19 at 18:56
• Please tell us if you free to use either XeLaTeX or LuaLaTeX or if you must use pdfLaTeX to compile your document. Also, please advise if you absolutely must use Arial, which is a clone of Helvetica, or if you are free to use Helvetica. (Hint: Only font geeks can readily distinguish Arial and Helvetica, and only if certain letters (chiefly uppercase-R) are present. – Mico Aug 25 '19 at 19:15
• If you want to use Times New Roman and Arial in PDFTeX, you can use winfonts. (I believe the bugs have been fixed?) There are also newtxtext/newtxmath and either uarial or tgheros as substitutes. – Davislor Aug 26 '19 at 5:14
• If you can, however, I would recommend fontspec or unicode-math. – Davislor Aug 26 '19 at 5:15