diff --git a/RELEASE_NOTES b/RELEASE_NOTES
index ea512b256..ac2cd230e 100644
--- a/RELEASE_NOTES
+++ b/RELEASE_NOTES
@@ -63,6 +63,7 @@ Bugs fixed
 - Bug 2414 - UdpSocket doesn't call NotifyConnectionFailed
 - Bug 2419 - BsmApplication should use RecvFrom and not SocketAddressTag
 - Bug 2425 - UdpSocketImpl simplification
+- Bug 2427 - 802.11ac selects wrong slot duration
 - Bug 2433 - Bic does not copy private parameters
 - Bug 2436 - SendBlockAckAfterAmpdu is called even if the A-MPDU frame is not addressed to the station
 
diff --git a/src/wifi/model/regular-wifi-mac.cc b/src/wifi/model/regular-wifi-mac.cc
index b79e897e8..ffc39c15e 100644
--- a/src/wifi/model/regular-wifi-mac.cc
+++ b/src/wifi/model/regular-wifi-mac.cc
@@ -1091,10 +1091,14 @@ RegularWifiMac::FinishConfigureStandard (enum WifiPhyStandard standard)
     case WIFI_PHY_STANDARD_80211ac:
       SetVhtSupported (true);
     case WIFI_PHY_STANDARD_80211n_5GHZ:
+      SetHtSupported (true);
+      cwmin = 15;
+      cwmax = 1023;
+      break;
     case WIFI_PHY_STANDARD_80211n_2_4GHZ:
       SetHtSupported (true);
     case WIFI_PHY_STANDARD_80211g:
-      m_erpSupported = true;
+      SetErpSupported (true);
     case WIFI_PHY_STANDARD_holland:
     case WIFI_PHY_STANDARD_80211a:
     case WIFI_PHY_STANDARD_80211_10MHZ: