Refueling after 20 minute hold

[DaveMc]

Hi All,

On flight EI 123 from Dublin to Chicago last Sunday the 14th of April. As we taxied to take off we held at the end of the runway for approximately 20 minutes whereupon the captain announced that there was a tech issue and we needed to return to the gate for the fix. It turn out to be one of the computers and after about 45 minutes we were on our way. During this time they refueled. I was curious that they required fuel after this period of taxing.
One other piece of info is that we had a long taxi and obviously had to repeat this again.
I am curious to understand the amount of fuel that would be consumed during this period. What percentage of the total would have been used?

This is not a question about safety, or cutting corners, or the pilots decisions and please understand that. I am just interested.

Thank you for taking the time to answer.

[Right Way Up]

Hi Dave,

Looking at your figures I would estimate he lost just over 5 minutes flight fuel. Making the initial fuel decision he would have added an amount (if any) over the minimum amount that he thought was required. Returning to stand he probably felt he still needed to depart with that figure and made good use of the delay to refuel. Sounds very reasonable to me.

[Di_Vosh]

Disclaimer: (I wasn't there, and I fly regional and not international)

Sometimes you have to depart with minimum fuel. When this is a requirement things like an extra 15 - 20 minutes on the ground can make a difference to how comfortable you feel.

So if there was a return to the ramp, utilising that time to top up seems a sensible thing to do.

[DaveMc]

I would like to thank you both for informative replies, and also to one other rely that now appears to have been deleted. It's funny how passengers think and what is actually going on up the front. It never even occurred to me that there might be a new flight plan due to the delay possibly resulting in more fuel required. Along with other reasons suggested. Interesting stuff.

[BOAC]

Perhaps a little more info on the 'legality', Dave.

There are minimum amounts of fuel required before you can 'legally' push back from stand. These include 'contingency fuel' which is for 'unexpected' events. It is permissable to use some of this 'contingency' on the ground in the event of an unexpected delay waiting to take-off, but if you have, and you had loaded near the 'minimum' figure to start with, then you could not 'legally' depart again after a return to stand - there are some options on flt planning which might help here - but if faced with a 20 min + 45 min delay, plugging into a bowser seems to be eminently sensible to all of us.

[blind pew]

There is also the possibility that he decided on a high speed cruise to try and make some of the delay up.