Always had a soft spot for the earliest V-tails. Ideally without the 3rd window. Not sure what year that came, but this looks like a factory install and not after market.
Jason: yes, it is. As some further examples, it is almost impossible to see the pitch trim indicator. And the wheel is in a weird position, too. The throttle, pitch and mixture controls are also out if sight, making it easy to grab the mixture as you are making your final power reduction on final…
But the trickiest bit remains the fuel management.
Wiiliam: yes, you are right. For me, it‘s an extreme thing, as I mostly fly the Cirrus, which, in terms of ergonomics and the sheer flying, is the easiest plane to fly out there. That‘s probably why, for a change, sometimes I do love flying these old „golden era“ birds so much.
Adam: from the factory, on the 35, the third small window came with the F35 (1955). The third long window came with the N35 (1961). But yes, many many early examples have later been refitted with more or bigger side windows.
Hi Boscomantico,
now I know who’s behind that Beech parked outside the hangar in EDFZ. My TB20 is parked just 50m away in the hangar. We met in EDGS in 2017 – I’m the one with the Jack Russell terrier. A few days ago I talked to a pilot who was working on that Beech and he asked me about my “still” British registration, was it you?
Today I was there but a seaplane was parked on your place. Hope to see you in EDFZ.
Good morning @nobbi !
For sure I remember! Hope you and the dog are doing well! Rheinhessen and Mainz (Drais, specifically) have in the meantime become a second home for me. What a beautiful area, particularly at this time of year!
No, it wasn’t me who you talked with. Likely the owner (Alex). The LA-4 is also his and is also available. Check it out here:
Back on topic: a very experienced and kind long-time K35 owner (with auxes and Osbourne tips as well) has reached out to me and has given me lot more valuable input. Although I don’t think anybody here operates this model / mod of airplane, I think it might still be interesting for the crowd, so I’ll copy it here. I don’t think anything like that would be certifiable these days…
To be candid I think fuel management on the K35 with Osborne tips very well may be the most challenging of any airplane, so I would do my best to commit it to memory. On the plus side, it has the greatest range of almost any other in it’s class: 1567 miles with reserve!
(per a previous owner, who claims it’s doable at 55% bhp; 6.7 gph;16.3 mp; 4.6 fuel pressure; 2300 rpm; and 14.12 hours endurance. (which is at least five times my bladder’s)
The main fuel valve switches sequentially between Off, Left, Aux, and Right tanks. The Aux position selects the two 10-gallon auxiliary tanks but, with the Osborne STC, now selects the output of two secondary fuel valves. The left (LH) auxiliary valve is an on-off valve for the left tip tank only. The right (RH) auxiliary valve selects between off, right tip tank, and the two 10-gallon auxiliary tanks. The two auxiliary tanks feed fuel simultaneously but with a differential of about two gallons. When one of the auxiliary tanks runs dry, the fuel valves must be changed to select another source of fuel. Never use the auxiliary tanks from any flight other than level flight; taking off on less-than-full auxiliary tanks will result in the unporting of the fuel supply and immediate loss of engine power.
While the tip tanks can both be selected to simultaneously supply fuel, most of the fuel will flow from just one tank. The uneven fuel flow will laterally unbalance the plane, making for less-than-optimal handling. The autopilot will not be able to track straight with one tip tank full and the other empty. See item 4 below.
From the Osborne STC instructions:
1. Use fuel from the left main tank until at least 10 gallons have been used. Fuel from the auxiliary systems may then be used; however, use only in level flight.
2. To use fuel from the tip tanks, turn the tip tank selectors to LH and RH tip tanks, and then turn the main selector valve to auxiliary position.
3. Recheck the left main quantity periodically and return to left main fuel anytime the left main gauge reads ¾ full.
4. Use fuel from both tip tanks simultaneously; however, one may be turned off for a period if an unsymmetrical load should develop.
5. When tip tank fuel has been used, turn main selector valve to a main tank. Turn LH tip tank selector to off position. The wing auxiliary tank fuel may then be used by selecting the auxiliary (20 gallon) position on the RH auxiliary selector and turn main selector to AUX.
6. When all auxiliary fuel is used, turn the main selector to a main tank and turn all other tank selectors to off.
7. If the tip tank fuel lines have been run completely dry in flight, air may be trapped in the line when the tip tanks are subsequently filled. This air pocket in the line may cause asymmetrical feeding of fuel from the tip tanks. To avoid this condition, operate power plant from each wing tip tank separately for a period of 1 minute during ground run-up.
Other notes:
Another means of purging air from fuel lines is to use the electric fuel pump prior to starting the engine. Set both throttle and mixture to minimum/cut-off to prevent fuel from getting to the engine and flooding it. Select only one tank at a time and run the fuel pump on High. The sound difference between liquid fuel and air is quite noticeable. This same technique is used for purging engine compartment fuel lines that may have vaporized fuel due to a hot engine.
Unused fuel from the right hand main tank is returned to the right hand main tank. All other unused fuel is returned to the left tank, so make sure there is sufficient room for it or else it will be dumped overboard.
Always keep aware of the left and right main tank fuel status. Since the left main is usually used for initial take-off, it is known to be able to supply fuel. It is good practice to test the right main tank, when safe, to insure it is also a reliable source of fuel. Should an auxiliary fuel starvation event occur than can’t be immediately rectified, switch to one of the known-good main fuel tanks to resume safe flight.
jesus that is complex indeed. And almost sure to catch out some people. I wonder how many forced landings with plenty of fuel on board have happened with this system…
I remember looking at a C model once. It only had the two mains and if I am not mistaken each of them had 6 USG unusable fuel, so the grand total of the 50 USG available from the mains came down to 34 usable. The range resulting from this is less than 300 NM with reserves so people started to get innovative. The Aux tanks will add about 1 hour approximately, so you need the tips to get a proper range airplane.
Somehow I think Beech got it wrong there in the first place. to have 12 USG unusable (1 hour of fuel) and then having a capacity which makes anything above 2.5 hours unrealistic was not a good standard fuel. And the aux tank developers just built on this. I agree, this could not and moreover should not be certifiable today, even though I have read about similar systems for Cessnas where also aux tanks feed into mains and the failure to do so has resulted in undesirable consequences.
In any GA plane, the ideal fuel system should have 2 wingtanks and a L/R and possibly both selector. Run on both should be standard with the L and R selections for imbalance corrections. If they add aux tanks, they should automatically transfer into the mains. In any event, all fuel tanks need gauges….
So maybe someone in the Beech crowd might gin up a nice little monitor which is capable of showing all tanks and maybe even re/design the fuel distribution system so that it becomes fail safe(er) than it is now.
boscomantico wrote:
The throttle, pitch and mixture controls are also out if sight, making it easy to grab the mixture as you are making your final power reduction on final…
I guess that will make the final power reduction….final.
Even if you grab the right lever for the throttle you should pull it slowly 
boscomantico wrote:
Empty weight on this one is a bit high at 938kgs, leaving (only) 400kg of useful load. (I am having some doubts on that weighing report).
I have collected W&B data for hundreds of Bonanzas. For the K model, I have 6 entries. The average empty weight is 2086 pounds or 946 Kg, so yours is real close to the average and only 6 Kg less. So it sounds very typical.
Mooney_Driver wrote:
I remember looking at a C model once. It only had the two mains and if I am not mistaken each of them had 6 USG unusable fuel, so the grand total of the 50 USG available from the mains came down to 34 usable.
The C model came with wing tanks of 20 gallon capacity or 40 total. Later on, 3 gallons in each tank were considered as unusable in all flight attitudes, so the capacity was reduced to 34 gallons. In level flight, you can burn the fuel until the engine sputters and therefore use 3 of the six unusable gallons. Later models had the capacity increased to 50 gallons (44 useable), then an optional set of aux tanks were added which provided an additional 20 gallons, 18 of which are useable. Finally, the fuel system was simplified with 40 gallon tanks in each wing and 74 are useable. In my 68 Bonanza, I have 74 gallons useable and range to exhaustion is over 6 hours.With an hour reserve, I have a no wind range of about 825 NM.
