Remove back seats for fuel cell?

[Badmoonraising]

I have a short body M20E. Is it a crazy thought to remove the back seats and install a fuel cell to extend my range? 

I really don't want to carry more than one person with me, besides, the back seats are so limited and cramped. Why have them?

It would be nice to have six hours of cruise  with a good reserve. And yes, a bottle "just incase". Okay, for sure, a bottle for pee. 

[larryb]

 

I agree on the back seat. Here is mine. It comes out easily and I had a custom carpet piece made for the space. I never use the back seat. Just the wife and I 99% of the time.

 

It would be nice to have a removable fuel bladder there for certain trips.

[Niko182]

Im just waiting for @Piloto to come here and talk about that pilot relief tube.

 

Regarding the actual question. Too mich fuel is never a problem as long as youre at or under gross weight. But having that back space for big luggage is great. Choose if you want people, luggage, or distance. Pick one of those 3. What other people would do is mostly irrelavent. Its your plane, your mission. 

Edited October 20, 2018 by Niko182

[carusoam]

I vote no for storing additional fuel inside the cabin...

It is already too close and not well separated from the cabin... where it is...

Check in with piloto he can fill in the details of adding additional fuel capacity and a p-tube in the event the p-capacity is too small...

Everything is good... until it isn’t good. Consider off field landings and escaping from the cabin...

Best tegards,

-a-

[Andy95W]

If memory serves, the original M20 and M20A had an auxiliary fuel tank located under the rear seat, since there isn't as much room in the wood wings for fuel.

If this is actually true, that would be a good place to start to get a field approval, using a factory design and factory parts, if you could find them.

Edit- Anthony's right about fuel in the cabin.  Weird.  Why not just get the Monroy long range tank option?  Already approved, just pay for the STC and get the work done.

[Hank]

Adding 12 gal to the wings is pretty easy and will preserve cabin space for baggage (my wife and I fill the back seat and baggage area to the ceiling when going away for a week or more, and when traveling around the holidays). My 52 gal provides 5-1/2 hours fuel plus reserve per the Owners Manual, and that's plenty for me--we are both ready to stand up and stretch after 4 hours. I've done 4:45 twice, and filled up with 41-42 gallons, leaving > 1 additional hour.

[1964-M20E]

I've done 5 hours with my F and still had 1 hour fuel left with the 54 gallon bladders.

[MIR2018]

14 hours ago, Niko182 said:

Too much fuel is never a problem as long as you're...not on fire! FTFY

   I think this is routinely done on Atlantic Ferry Flights... Could be wrong, but I vaguely remember it being done on at least one Mooney, when I used to broker back in the 80's...

 

[carusoam]

Turtlepac and ferry flights go together...

One off type of flying has some elevated risk associated with it...

Having a turtlepac in the cockpit for every flight would add some stress...

Best regards,

-a-

[Niko182]

Also to add, Its gonna be a really small auxiliary tank you're gonna be adding. a 20 gallon tank will get you 74 gallons total, allowing 8.7 hours of total flight no reserves at 8.5 GPH.
a 20 gallon tank could fit without you even removing the back seats.

[kortopates]

Don't confuse ferry tank fuel cell installations, which are entirely limited temporary operations, as being suitable for "permanent" fuel cell installations - since they are not. Ferry tanks don't typically meet the requirements for ensuring the occupants can otherwise survive  an emergency off field landing. Excuse my poor wording, but actual requirements can be reviewed in Part 23.2430 to give you an idea of what you would be up against. Thus sticking to the wings is your only real practical solution.

[Badmoonraising]

Excellent points here. Yes, come to think of it flying around in a gas filled cockpit does't sound good at all. Adding tanks to the wings sounds like a very expensive proposition. Better to live with what I have. 

[carusoam]

If there were a lower cost or a better way...

an MSer would be pointing it out...

His name is piloto! 

Best regards,

-a-

 

[Bob_Belville]

I have 64 gallon O&N (now Griggs) bladders in my '66E. For long non-stop trips I run ~ 8 GPH, LOP, 140+ ktas. That's roughly 900 nm with IFR reserves.

[kerry]

The A model does have a 14 gallon tank under the rear bench. I've seen these auxiliary tanks available online.  It would be interesting to know what space is available in a metal wing to drop in a metal tank.  By the way I have to remove my  rear tank every year as a recurrent AD so I can inspect my wood spar.

[cliffy]

Long way to go from a temporary ferry install to an approved full time install. Way too much cost and FAA paperwork. 

Any added fuel tanks also have border crossing restrictions   Go with the bigger gas bags- all the FAA work is already done.