diff --git a/gr-air-modes.spec b/gr-air-modes.spec
index 46673e3..5bd7727 100644
--- a/gr-air-modes.spec
+++ b/gr-air-modes.spec
@@ -8,12 +8,20 @@
 Name:             gr-air-modes
 URL:              http://github.com/bistromath/gr-air-modes
 Version:          0
-Release:          0.65.%{git_suffix}%{?dist}
+Release:          0.66.%{git_suffix}%{?dist}
 License:          GPLv3+
 BuildRequires:    cmake, gcc-c++, python-devel, numpy, scipy, gnuradio-devel
 BuildRequires:    sqlite-devel, uhd-devel, boost-devel, doxygen, graphviz
-BuildRequires:    swig, PyQt4-devel, qwt-devel, python-zmq
-Requires:         numpy, scipy, PyQt4, PyQwt, python-zmq
+BuildRequires:    swig, PyQt4-devel, python-zmq
+# PyQwt dropped in f31+, upstream ticket suggesting migration to PyQtGraph:
+# https://github.com/bistromath/gr-air-modes/issues/104
+%if 0%{?fedora} < 31
+BuildRequires:    qwt-devel
+%endif
+Requires:         numpy, scipy, PyQt4, python-zmq
+%if 0%{?fedora} < 31
+Requires:         PyQwt
+%endif
 Summary:          SDR receiver for Mode S transponder signals (ADS-B)
 Patch0:           gr-air-modes-modes_gui-traceback-fix.patch
 Source0:          https://github.com/bistromath/gr-air-modes/archive/%{git_commit}.tar.gz#/%{name}-%{git_suffix}.tar.gz
@@ -86,6 +94,9 @@ rmdir %{buildroot}%{_docdir}/gr-gr-air-modes
 %doc %{_docdir}/%{name}/xml
 
 %changelog
+* Mon May  6 2019 Jaroslav Škarvada <jskarvad@redhat.com> - 0-0.66.20160831git3bad1f5d
+- Dropped PyQwt in f31+
+
 * Wed Apr 24 2019 Jaroslav Škarvada <jskarvad@redhat.com> - 0-0.65.20160831git3bad1f5d
 - Rebuilt for new gnuradio