Buying a Plane -- Engine vs Avionics vs Price

[Mr.T]

Interesting. I’ve never flow a AA5 or any Grumman( I really want to.). Do they not climb well in the summer or are they just really hot inside because of the canopy? I’ve always thought of them as ideal single engine planes since they go fast, are fixed gear, and burn little gas.

One of the most compelling reasons to buy a Grumman is the sliding canopy - you can open it about 3 or 4" in flight and get incredible air circulation; on the ground, you can slide it all the way back and look like a cool fighter jock as you taxi around with your hair blowing in the breeze. They're incredibly sporty, fun planes to fly. Visibility is great, too.

For a 150hp plane, the AA5 (and AA5A) are fast and efficient. But - compared to a 180hp plane like the Tiger - they just don't climb worth a darn in the heat of summer when the DA starts to rise. You might start off with 400 or 500 fpm but by the time you get up to 6000 ft, you're lucky to see 250 or 300 fpm. I had plenty of days in my AA5 where gross weight takeoffs had more pucker factor than I was comfortable with.

So for me, it's a no-go; maybe if I find an AA5A with a Powerflow exhaust *and* the 160hp STC, I'll consider it (there are several on the market now). But more than likely, I'll hold out for an AA5B or - more likely - a M20C.

 

[Juliet Hotel]

I rented an AA5 a few times. My wife was not a fan of the sliding canopy because of the lack of sun protection. Sliding the canopy open cooled everything off but didn't do anything about UV skin exposure. In an owned plane I suppose you could rig up some kind of shade like the RV guys do, but in a rental... Well like I said, she wasn't a fan.

 

[Rcmutz]

You have to open up the engine to do the HC upgrade, so you'd want to wait until it's overhaul time. Another option is the PowerFlow Exhaust. It's a tuned exhaust system, and is supposed to either increase the available power by 30%, reduce fuel consumption by 30%, or some combination of the two. A big advantage is you don't have to open up the engine. I have no relationship whatsoever with PowerFlow Exhaust, just think it looks like a great way to get more power, more efficiency, or some combination of the two. Just internet search for PowerFlow Exhaust.

Not correct! The HC STC does NOT require yo to open the case. You can purchase the cylinder kits from Lycoming or elsewhere, and install. The STC is $500. This is what I did on my ex-cheetah. $6000 all in, cylinders, STC. R&R of cylinders.

 

[alfadog]

Not correct! The HC STC does NOT require yo to open the case. You can purchase the cylinder kits from Lycoming or elsewhere, and install. The STC is $500. This is what I did on my ex-cheetah. $6000 all in, cylinders, STC. R&R of cylinders.

That's not bad, especially if you can use the top overhaul.

 

[flyingcheesehead]

To the original question: You'll generally get most of what you put into engine overhauls back out upon resale, minus what you fly off of it. Avionics, maybe half, though there seems to be a bonus for Garmin and a penalty for other stuff IME. Paint and interior, it depends, but you probably won't get a ton back out of them. Airframe mods, basically zero.

So, buy the plane that looks great and has an avionics stack that'll keep you happy for a good long while, and a run-out engine, and keep enough money in the bank for an overhaul. Anything more you get out of the engine is just bonus/free time.

 

[hindsight2020]

To the original question: You'll generally get most of what you put into engine overhauls back out upon resale, minus what you fly off of it. Avionics, maybe half, though there seems to be a bonus for Garmin and a penalty for other stuff IME. Paint and interior, it depends, but you probably won't get a ton back out of them. Airframe mods, basically zero.

So, buy the plane that looks great and has an avionics stack that'll keep you happy for a good long while, and a run-out engine, and keep enough money in the bank for an overhaul. Anything more you get out of the engine is just bonus/free time.

Indeed, which is why the dreamers on TAP et al listing those clap traps laden with Narco panels and GX-55/155/300 navigators, are screwed. I really used to be indifferent to avionics since I have enough recency at work that I can do what most weekend warriors struggle with a Gar-mart airliner panel, on a KLN 89B, a vacuum six pack and the seat reclined while playing angry birds partial panel lol. Then I pivoted into the Arrow 5 years ago and fast forward to today and holy crap, I wouldn't sink a nickle in the panel given what avionics cost (part of it is squarely our fault as a collective, willing to overpay for dumb electronics that don't increase your climb rate, true airspeed or useful load).

Which is another of way of saying you're 100% correct: avionics are indeed a higher opportunity cost compared to engine costs, which is why it pays to purchase as-installed already, and stop obsessing about engine times. Granted, easier for someone like me to say, as someone who has flown aggressively post TBO and is not afraid to do so, nor to happily own on a "on condition" basis. Everybody has their own risk tolerance to contend with of course. I second your comment. Put me in the camp of the runout engine while stealing the avionics candy from the baby selling me the airplane. The opposite is not true for me, especially as someone who doesn't view a low SMOH low calendar use engine as a higher value (let alone more reliable) proposition than a high SMOH high calendar use counterpart. Not saying I would pay a premium for the latter, but I guarantee you I'd exercise higher liquidity of transaction for it as a buyer. Again to each their own.

 

[chemgeek]

Interesting. I’ve never flow a AA5 or any Grumman( I really want to.). Do they not climb well in the summer or are they just really hot inside because of the canopy? I’ve always thought of them as ideal single engine planes since they go fast, are fixed gear, and burn little gas.

The AA5 climbs like any other 4 seat plane in this hp class. With the HC STC jt is a strong climber, and even better matched for cruise and climb with the Sensenich prop STC. With two on board plus luggage and full fuel it will maintain 500 fpm through 10,000 feet easily. Not so the stock engine.

The canopy is not a full glass canopy like the AA1 series, but rather has a center span roof. Vis is good, though. In the AA1A I had you broiled in summer, but the view was stupendous.

 

[hindsight2020]

OP, fixed pitch 160/180 hp airplanes are going to leave you very underwhelmed in climb. I know the siren song of cruise speed, but you really need to give constant speed prop and airplanes with a better power loading for your payload mission a try. Even a midget seat 235 will blow the pants off these 4 bangers. I ferried two of my wife's friends (large people) on the Arrow a month or so ago with full fuel, and though it doesn't encompass the majority of my mission (and hey, beggars can't be choosers), I was absolutely underwhelmed of how terrible it performed compared to light weight.

I mention power loading because airplanes like the six 260, have good amount of HP yet the power loading makes them worse performers. Constant speed props are not going to eat you out of house and home. And I have one with a stupid 100 recurrent AD on it mind you.

 

[Mr.T]

OP, fixed pitch 160/180 hp airplanes are going to leave you very underwhelmed in climb. I know the siren song of cruise speed, but you really need to give constant speed prop and airplanes with a better power loading for your payload mission a try. Even a midget seat 235 will blow the pants off these 4 bangers. I ferried two of my wife's friends (large people) on the Arrow a month or so ago with full fuel, and though it doesn't encompass the majority of my mission (and hey, beggars can't be choosers), I was absolutely underwhelmed of how terrible it performed compared to light weight.

I mention power loading because airplanes like the six 260, have good amount of HP yet the power loading makes them worse performers. Constant speed props are not going to eat you out of house and home. And I have one with a stupid 100 recurrent AD on it mind you.

Good points, all. Maybe I've been considering a 180hp Tiger to be "pretty much" the same as a 180hp M20, when clearly that's not the case in a dozen ways.