Nav Controller pop toolbar button disappears then reappears

I have a button in my ionic 2 footer. It slides ok with push but not with pop and a back transition. It disappears then reappears and doesn’t look great. How can I get it to slide like the forward transition does?

<ion-footer class="has-back-btn">
  <ion-toolbar class="no-padding transparent">
 <ion-buttons start>      
<button class="back-btn" tappable (click)="goBack()" ion-button icon-left>
 <i class="fa fa-chevron-left " aria-hidden="true"></i> Back

 goBack() {
  var navOptions = {
      animation: 'ios-transition',
      direction: back,
      animate: true,

  if(this.isModal == true){

here is a screen shot