Evaluating potential purchase

Jaybird180

Final Approach
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Jaybird180
I am setup to look at a C172 buy-in. I plan to test fly it soon. What maneuvers should I be sure to fly as I check rigging, etc? I will sit right-seat due to PIC (insurance) issues. Any advice?
 
No A&P here but I'd do a control slack test. If you don't know what it is, it's really just a positive control test as done by glider pilots. You have someone grab the surface and you gently apply pressure to see if there is slack. The person on the outside (preferably another pilot) should tell you when the surface starts to move. They should tell you at the first sign of positive pressure. They check for movement in both directions and should use fingertip forces.
 
If it flies straight and level its rigged. Skyhawks arent G5s. They are quite simple machines. What year is it and what engine does it have?
 
First, try to fly a trip of sufficient distance that you have time to sit and watch without being hurried. A short X/C is much more valuable than flying around the patch. During taxi and takeoff/landing roll, note any indication of shimmy, tire vibration, other irregularities of tires, wheels, brakes, linkages.

Monitor start procedures, check for proper operation of mag and master/alternator switches. Ask to see separate functions of master switch. Pay careful attention to mag drop, compare to EGT if possible. Insure that prime and other start procedures are consistent with normals for other airplanes of same make/model.

Check to see that everything installed in the plane works in flight. Nav's, Comm's, audio panel, GPS, transponder, gyros, heats, vents, defrosts, mixers, lights, autopilot (check each function) etc. Work your way across the panel and test everything that you see. Ask tower or ATC if the transmitters work.

Check for air leaks, fit and seals of doors and windows. Check wing-root vents for proper seal and fit. Check all interior airflow louvers, outlets and plumbing for proper flow.

Check static and max RPM's for values, all gages and indicators, including all EGT/CHT functions. Check vacuum and electrical volt/load/ammeters for proper indication, use pitot heat to change load. Check all gages in cluster for proper operation. Note oil pressure and temps during various phases (after start, in cruise, reduced power, taxi after touchdown.) Check brakes on both sides for proper operation, equal pressures.

Establish cruise to determine if the plane flies straight (pick a point on the horizon) and level (check for hands-off wing-drop) and true (ball centered). Compare visual references to gyro indications. Does visual wings-level agree with attitude instrument? Check flap extension at all positions to determine any asymetric issues. Check slow flight for stall warning operation. Execute a stall to check wing-drop.

Check ASI for approximate speed, compare to other sources (three course GPS test). If possible, start with full tanks and do post-flight top-off to determine burn from each tank. Check seats, door handles, door locks, window locking levers, other moving parts for proper operation.

During shutdown, check for RPM rise during leaning to cutoff.

I am setup to look at a C172 buy-in. I plan to test fly it soon. What maneuvers should I be sure to fly as I check rigging, etc? I will sit right-seat due to PIC (insurance) issues. Any advice?
 
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If you get a chance to fly it, spend some time and see if the plane is easy and comfortable for you to fly, that you don't have to fight the controls or get fatigued quickly because of a poorly rigged airplane.

It is important to have ALL of the logs, both airframe and engine logs, for the aircraft, and you should be able to have access to them and time for you and your A&P to review them carefully before making any purchase...there are ALOT of 172's out there on the market: don't fall in love with any plane. Just my 2 cents.
 
I test flew a piece of junk Warrior a few years back. I was still a student so I was flying with the seller in the RS. It ran hot in a long climb, it almost went inverted when I attempted a 45 degree steep turn, it just kept going when I tried to stop the rate of bank. The pre buy inspection exposed large hunks of lead in the engine. I didn't buy it.

John
 
It's a 98 SP analog gauge model. I am happy with the log review and just have never flown (in) it. Thanks for the brake and vents reminder.

Will the ground pre-takeoff control check provide the same info as a slack test?
 
Jay, I call BS on the right seat and insurance. The insurance could not care less which seat the PIC sets in as long as it is a front seat with full controls.
 
It's a common ploy and not worth arguing about. If he's evaluating everything on the airplane he's better situated in the right seat anyway. Many of the gages and controls he will want to check are on that side anyway, and there's no way to feel around for airleaks and peer around at all the hardware if you're flying the plane. He can learn everything he wants to know about handling qualities by flying it for about 10 minutes.



Jay, I call BS on the right seat and insurance. The insurance could not care less which seat the PIC sets in as long as it is a front seat with full controls.
 
I agree, but it is still BS. If he will BS about that what else is BS?
 
Nothing that the seller says should be taken as gospel. I care a lot about the airplane, records, history and operational condition, but don't give a rats about the insurance coverage. Big waste of time to chase that rabbit.

I agree, but it is still BS. If he will BS about that what else is BS?
 
It is important to have ALL of the logs, both airframe and engine logs, for the aircraft, and you should be able to have access to them and time for you and your A&P to review them carefully before making any purchase...there are ALOT of 172's out there on the market: don't fall in love with any plane. Just my 2 cents.

What do you really want to see when you inspect the maintenance records ?
 
What do you really want to see when you inspect the maintenance records ?
"Proper" entries which include date, signature, and certificate number as well as specific language. Matching serial numbers. Entries which support seller's narrative. No gaps in chronology. I really like to see the same A&P from yr to yr...otherwise, if the plane hasn't changed base I wonder why the mx is being "shopped".

One plane I looked to buy the owner claimed an autogas STC but I found no entries to support that. Another plane I wanted to buy the A&P did not include specific language with respect to complying with ADs. Is the annual condition inspection complete if ADs are not complied with? No, so why was the annual signed off but that specific language was not included in logbook entry?
 
It's a common ploy and not worth arguing about. If he's evaluating everything on the airplane he's better situated in the right seat anyway. Many of the gages and controls he will want to check are on that side anyway, and there's no way to feel around for airleaks and peer around at all the hardware if you're flying the plane. He can learn everything he wants to know about handling qualities by flying it for about 10 minutes.
When plane shopping I let them fly for the first flight. That allows me to observe and move around the cockpit for precisely the reason you mention.
 
What do you really want to see when you inspect the maintenance records ?

What my A&P's reation is to what he finds in the logs....just like I have done for the planes I have turned down, and the ones I have purchased.

For an hour or so of his time and a cup of coffee or two, we sat down together, looked over the logs, especially for AD compliance and damage history, TTAF SMOH STOH TSPOH and hours flown each year, he made some notes for me, gave an opinion about the history of the aircraft, pointed out areas I should question, and gave me an opinion about whether or not to go ahead with a pre-buy: the value was priceless.
 
When plane shopping I let them fly for the first flight. That allows me to observe and move around the cockpit for precisely the reason you mention.

It also gives you an opportunity to see if they have some major faults in their operating procedure that may indicate higher wear on the engine. In a Skyhawk, that's pretty hard to do, but it is more relevant as you move to aircraft with bigger, more powerful engines and tighter cowls.
 
The perpetual skeptic, eh?
I agree, but it is still BS. If he will BS about that what else is BS?

although my risk is limited to $2500. I intend to use this as a learning experience to prepare me for larger risk, but a per-buy is not practical for a buy-in that has been in continuous operation.

I cannot be PIC until I am on the policy and my $ must precede being added to the insurance. One of the owners is taking me up and if he offers left seat, I'll take it, but would never ask another PP for his seat.
 
I agree, but it is still BS. If he will BS about that what else is BS?

How does the seller know the buyer is truly serious and not just looking for some free flight time? Or a tire kicker?

I'm with Wayne - I wouldn't care about whether or not the seller gave me left seat. I also wouldn't believe the seller any more or less for it.
 
The all important log book inspection is useless with out the aircraft to inspect. You wouldn't even know if the logs in hand apply to the aircraft, you couldn't do an AD check with out a complete inventory of the equipment installed, or the visual inspection to see if the ADs were in fact complied with.

The major things to look for in the maintenance records are the time of components, are any time lifed items being tracked properly, is the time given correct? Is the engine the proper one for the aircraft make and model? Is the engine overhaul returned to service entry, one that meets FAR 43.2 for "0" since major ? Is that entry backed up with a work order that actually says what was done to the engine during overhaul?

Log books are not written in Greek, the owner that has completed their home work properly can and in my opinion should be able to read them and find the information they need to determine the material condition of the aircraft.

Every AD is now on line at several places, there is no reason the buyer can't get that information. Years ago when the A&P-IAs were required to buy the microfiche subscription yes, you had to get an A&P-IA involved, no so any more.

Every aircraft's history records are available to the buyer, you should have them for any aircraft that are inspecting.

An hours conversation with the last A&P-IA that signed off the last annual will be more useful to you than 10 hours with your nose in the logs. If they are an idiot act accordingly.
 
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How does the seller know the buyer is truly serious and not just looking for some free flight time? Or a tire kicker?

I'm with Wayne - I wouldn't care about whether or not the seller gave me left seat. I also wouldn't believe the seller any more or less for it.

I know that my Aircraft isn't the average spam can, but my insurance will not cover any pilot but me, open pilot warrantee does not apply to my aircraft, you had best investigate the coverage on the aircraft before you become the PIC, because any damage you create, you might be required to pay out of pocket to repair, and end up buying the pile of junk you don't want.
 
Jay, I call BS on the right seat and insurance. The insurance could not care less which seat the PIC sets in as long as it is a front seat with full controls.
However, the seller may not be comfortable being PIC from the right seat with someone s/he's never met before occupying the left seat, and I would call that prudence, not "BS." Not every PP is as comfortable in that situation as a CFI like you or me.
 
If logs are complete and maintained in an orderly manner, that's a pretty good start. A review of each log will show the "big stuff" that has been done over the years, because we all know that if it's not in the logs it didn't happen.

In today's world, a careful analysis of STC's and 337's is (or should be) a focus of any records review, as well as comparison of the on-site 337's to those on the FAA's data base. They won't always agree, but at least you can approach the transaction with both eyes open as to the potential issues.

The all important log book inspection is useless with out the aircraft to inspect. You wouldn't even know if the logs in hand apply to the aircraft, you couldn't do an AD check with out a complete inventory of the equipment installed, or the visual inspection to see if the ADs were in fact complied with.

The major things to look for in the maintenance records are the time of components, are any time lifed items being tracked properly, is the time given correct? Is the engine the proper one for the aircraft make and model? Is the engine overhaul returned to service entry, one that meets FAR 43.2 for "0" since major ? Is that entry backed up with a work order that actually says what was done to the engine during overhaul?

Log books are not written in Greek, the owner that has completed their home work properly can and in my opinion should be able to read them and find the information they need to determine the material condition of the aircraft.

Every AD is now on line at several places, there is no reason the buyer can't get that information. Years ago when the A&P-IAs were required to buy the microfiche subscription yes, you had to get an A&P-IA involved, no so any more.

Every aircraft's history records are available to the buyer, you should have them for any aircraft that are inspecting.

An hours conversation with the last A&P-IA that signed off the last annual will be more useful to you than 10 hours with your nose in the logs. If they are an idiot act accordingly.
 
In today's world, a careful analysis of STC's and 337's is (or should be) a focus of any records review, as well as comparison of the on-site 337's to those on the FAA's data base. They won't always agree, but at least you can approach the transaction with both eyes open as to the potential issues.

I should have been more clear when I said, "
Every aircraft's history records are available to the buyer, you should have them for any aircraft that are inspecting."

that is why you need the CD from OKC.
 
However, the seller may not be comfortable being PIC from the right seat with someone s/he's never met before occupying the left seat, and I would call that prudence, not "BS." Not every PP is as comfortable in that situation as a CFI like you or me.

There is a point here that many CFIs and pilots setting in the right/back seat when a pilot new to the aircraft is acting PIC in the left/front seat.

and that is simply either pilot can add too much braking action and all the other pilot can do is add more brakes or knock the other out.

This is not just a tail wheel accident, I know of about 5 aircraft that this happened to, the tricycle gear left the runway, and hit some thing, the tail wheel aircraft nosed over.
 
I flew it yesterday.

I think I have decent standards of expectation and it was really nice. Seemed to have lower noise levels than the P models I'd been flying. All the vents seal up nicely, no breezes around the door/window seals, etc.

Hands-off S&L will fly for a few seconds before a slight left roll. I suspect he had some left rudder in (looking at his feet and feeling his imputs), as when I took the controls, I had to input (very light) left aileron pressure for S&L (from the right seat).

Can this be trimmed (rigged) out?

The pilot I flew with said he flight plans at 110kts (ouch) but gets 8.5GPH.
 
I agree, but it is still BS. If he will BS about that what else is BS?

Maybe the seller is your average joe PP and is not comfortable flying the airplane from the right seat.

I'm sure I could fly and land tolerably from the right seat but I would not want to assume the responsibility of PIC from the right seat if I didn't have to.
 
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I'm reasonably proficient in my 170 but I haven't flown it from the right seat since my prepurchase test flight in 2006. I wouldn't want the second time to be with a strange pilot I've never met before in the left seat, just because he might want to buy it.
 
Hands-off S&L will fly for a few seconds before a slight left roll. I suspect he had some left rudder in (looking at his feet and feeling his imputs), as when I took the controls, I had to input (very light) left aileron pressure for S&L (from the right seat).

Can this be trimmed (rigged) out?

Probably. It's a crapshoot if the plane was properly rigged last time any major adjustment was made or control surface was reinstalled. There is a specific procedure. That being said a slight tweak of the rudder tab might be enough ;)

Even for a SP 110 knots sounds about right. It's still a 172.
 
The pilot I flew with said he flight plans at 110kts (ouch) but gets 8.5GPH.

Our club's 172N with the Penn Yan 180 hp conversion specs out at 114 kts at 65% power. Planning for 110 kts isn't a bad thing to do. I'd rather arrive slightly early than have to call FSS to amend a VFR arrival time.
 
The pilot I flew with said he flight plans at 110kts (ouch) but gets 8.5GPH.
I plan for about these numbers in Cherokee 140 (pictured in my forum avatar). Really it's more like 8.2 gph, but book says 8.5 for some reason - maybe our typical cruising altitudes to it. The book also promises 120 kts which is fantasy.
 
I flew a couple of 172S's from VA to Chicago, MI, GA and the like a lot. On those xc trips, I planned for 115kts true, and 8.5 gal/hr. I went high every time. As high as I could. Sometimes I would have a slightly higher TAS, never more than 120, (though one time I was getting GS of 170+.) Every time I filled the tanks I could almost divide the gal pumped by hobbs reading and come out within .1 of 8.5 gal/hr. With 53 gal, I only figured 5 hrs fuel in case of higher fuel burn, but I never experienced it on those trips. Shorter flights, I'd figure on 10/hr. I guess leaning practices were different for pattern stuff or practice area etc.

They're good airplanes. I liked having the use of them, did what I wanted really well. I'd never buy one though. Just personal preference. 182 maybe, but not 172.
 
JayBird, how big a chunk of ownership are you buying? If it is minor don't worry about all the worrywarts on here and just go with your gut...

If it is a major financial hit, then pay an independent A&I (you want one with inspection authority) to do a full prepurchase inspection...

A Hawk is a wonderful airplane, simple, efficient, and as safe an airplane as ever built... Even though I own a twin, every time I fly a Hawk I sit there and grin... It's just plane fun to fly (pun intended)

denny-o

You cannot go wrong with a Hawk that is maintained...
 
Not enough to fret over any risk. But since this is my first ownership, I want to develop the owner mindset that accompanies it, which is the only reason for the extra steps.
 
typically I plan for 9gph and 115kts, but as others have said its closer to 8-8.5gph.

Also, we want pictures !
 
It's now a done deal. Paperwork signed and money exchanged hands.
 

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I'll have to check my log when I get home, but I do believe that plane has my fingerprints on it....and it's not likely to be it's last entry.

Congratulations!
Fixed that for ya
 
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