Do POH's ever get updated/revised with new info?

Will Kumley

Will Kumley

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I like to create my own checklists for the planes the local airport has to rent. I use the checklist they provide as a template for many of the things but still verify info via the POH and sometimes reorganize to what I consider better for me.
One plane is a C-172M and its airspeed indicator indicates knots per hour instead of miles per hour. Not a big deal and conversions are super easy with my fancy E6B. I've noticed a few errors in their conversions but also noticed on the V-speeds table that they have Va speeds up to a gross weight of 2,450 pounds. As far as I can tell the 172M has a max gross weight of 2,300 pounds.
A 172R has a max gross of 2450 and I'm thinking they copied the data or format from their R series plane and converted the numbers but want to make sure I'm not going nuts here. I know I can just look at the POH they have but right now I have no need or reason to drive out to the airport. I will email them to ask their input. But if anyone on here is aware of POH's getting revised then maybe I haven't found the right POH online. And with it being Sunday I likely won't get a response from anyone at the airport today.
 
They sure do. Beech's products have a subscription, it's about $100/yr.
 
Yes, they do all the time in the newer acft, and some time the older if is something very important. Your POH that you keep in the acft, as an addendum should also have some additional information as things get added / changed.
 
My 182P was originally in miles per hour. I prefer to work in knots, and changed the airspeed indicator to a later model with dual range indicators in MPH and KTS. All v-speeds and ranges were identical. A&P made log entry for minor modification. Since original POH and the STC’s were in MPH, Just did not want to run against issue (inspection, regulation, insurance claim) down the road cause trouble if no MPH was displayed. Elected to change the MPH ASI to dual display with knots on the outside and MPH on the inside.


My ship also has significant engine and airframe modifications altering the overall performance of the aircraft. I created my own POH with all of the mandatory STC changes to the original document. I still fly with the original POH and flight supplement manuals required. For me it was easier to have one linear POH with all of the edits from the STC’s Included which superseded much of the original checklist, performance data, preflight, etc.; rather than at sometime of need, thumb through three or four different documents.
 
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Which is why you have a POH for a specific airplane, and why that POH is worth its weight in gold. If it ever got lost it would be nightmare, as it contains all the modifications throughout the years, that airplane's unique weight, etc.
 
Also there are some POH changes that are driven by AD’s. Cessna has never touched the old POH’s. It’s up to the aircraft owner to make the POH modifications due to AD’s or STC‘s as directed in those docs.
 
There are POH revisions...............yes. But you don't have to do the revision unless it is mandated by an AD.

For instance, about 30 years ago beech revised ALL their POHs to remove the short field takeoff procedure. There was no AD.............so you would want to keep that in place to prevent THIS! This is a Mears Field at 270 ft in Washington State. Had he used takeoff flap setting, as the older Bonanzas had in their POH it would have been eezy peezy.

 
Aircraft POH change all the time. It might be a model POH change, such as those mentioned: ADs, modifications requiring a Supplemental Type Certificate.

But there is a very common one these days often overlooked - the effect of glass panels and new avionics. All of that added, updated equipment generates an AFMS - Airplane Flight Manual Supplement, which is a mandatory item (whether or not the airplane original required a POH at all).

I recently had a great example of this. The Diamond DA-40 XLS, with the G1000, uses the exact same POH as the stock non-G1000 airframe. The only differences are reflected in the AFMS, including the ones for the G1000, the GFC 700 autopilot, and the Hartzell 2-bladed prop. We have one in a flying club where I am an instructor. One of the other instructors wrote the club checklist and the club quiz. I pointed out a number of errors in both. He wrote back, "Read the POH!!" I replied, "Read the right parts of the POH." He had taken the checklist items and quiz answers from the "stock" and didn't check the AFMS. That led to discrepancies on such things as as limitations on max continuous power (and a checklist item to reduce power for enroute climb) and even how much fuel was actually displayed on the fuel gauges.
 
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kgruber said:
There are POH revisions...............yes. But you don't have to do the revision unless it is mandated by an AD.

For instance, about 30 years ago beech revised ALL their POHs to remove the short field takeoff procedure. ]
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Mooney did the same with the J model.
 
I flew an A/C that got its TC in the late 70's. Around the early 90's the flight manual was revised for several minor details. One detail was if you lose an autopilot, you must reduce Vne.
 
To answer the question posed in the subject line: Yes, all the time. And it can be specific to make/model, serial range, or individual aircraft. That's why each aircraft has its own unique POH that must stay in the airplane to be legal.

Will Kumley said:
I like to create my own checklists for the planes the local airport has to rent. I use the checklist they provide as a template for many of the things but still verify info via the POH and sometimes reorganize to what I consider better for me.
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Great idea! I'd suggest that you find a good CFI who is experienced in type to go over your changes with you as well. But yes, I've made many of my own checklists and I think it's not only a valuable exercise, you also end up with better checklists in the end.

One plane is a C-172M and its airspeed indicator indicates knots per hour instead of miles per hour. Not a big deal and conversions are super easy with my fancy E6B. I've noticed a few errors in their conversions but also noticed on the V-speeds table that they have Va speeds up to a gross weight of 2,450 pounds. As far as I can tell the 172M has a max gross weight of 2,300 pounds.
A 172R has a max gross of 2450 and I'm thinking they copied the data or format from their R series plane and converted the numbers but want to make sure I'm not going nuts here.
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This sounds very suspicious to me. If the POH in the plane shows the wrong weight and balance info or limitations, and you take that plane to a checkride, you may find that you've failed the checkride before you even get off the ground. Definitely ask the flight school about the status of the POH on that airplane and why those discrepancies exist.

Also, as @midlifeflyer noted, be sure than when you're making your checklists, you look at all of the Aircraft Flight Manual Supplements for any STCs the airplane may have installed. Those often modify or add to checklist procedures, and especially in an emergency you can't possibly go through all of the AFMSs to find what the procedures ought to be. As he noted, the DA40 is a "frequent offender" here - I think it has something to do with airplanes initially certified by EASA, they really try hard not to modify the original type certificate and they do everything via "modifications" even though those modifications may be installed at the factory. The (EASA-certified) TBM is the same way.
 
Thanks for all the reply’s. I’ll hit up the airport tomorrow to verify the checklists they provide is accurate. However, I still have a sneaky suspicion someone just goofed when making a bunch of checklists. Even found a couple references to MPH on it.
 
Will, knots is a measure of speed. It means “nautical miles per hour”. Knots per hour is a measure of acceleration...

-Skip
 
Will Kumley said:
I like to create my own checklists for the planes the local airport has to rent. I use the checklist they provide as a template for many of the things but still verify info via the POH and sometimes reorganize to what I consider better for me.
One plane is a C-172M and its airspeed indicator indicates knots per hour instead of miles per hour. Not a big deal and conversions are super easy with my fancy E6B. I've noticed a few errors in their conversions but also noticed on the V-speeds table that they have Va speeds up to a gross weight of 2,450 pounds. As far as I can tell the 172M has a max gross weight of 2,300 pounds.
A 172R has a max gross of 2450 and I'm thinking they copied the data or format from their R series plane and converted the numbers but want to make sure I'm not going nuts here. I know I can just look at the POH they have but right now I have no need or reason to drive out to the airport. I will email them to ask their input. But if anyone on here is aware of POH's getting revised then maybe I haven't found the right POH online. And with it being Sunday I likely won't get a response from anyone at the airport today.
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On a Cessna 172M? Practically never. In fact the current publications have been revised once.

That being said, the operating limitations may change depending on aftermarket equipment installed, Cessna doesn't know or care about those so its up to the approval holder to supply the amendment at the time of purchase. Need to know what serial number you have when ordering from the mothership. They can also be changed via airworthiness directives.

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Skip Miller said:
Will, knots is a measure of speed. It means “nautical miles per hour”. Knots per hour is a measure of acceleration...

-Skip
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Wait, are you saying they are not the same thing? I was using the term interchangeably. I understand Knots is a measure of speed.

The real reason this whole thread got started though was more from the change in max gross weight on the checklist. The knots was a trivial addition to the conversation but also why I started verifying numbers and data as I saw things that didn't look right on the surface.I can convert MPH to knots easily. I just couldn't realistically see how the aircraft max gross weight would increase by 150 pounds. In theory I could see an engine upgrade allowing it, but I'm sure there is more to it than just an engine upgrade when it comes to determining max gross weight. I've worked on aircraft for 20+ years, but fixing planes, and designing/determining limits is two totally different things.
 
bnt83 said:
On a Cessna 172M? Practically never. In fact the current publications have been revised once.

That being said, the operating limitations may change depending on aftermarket equipment installed, Cessna doesn't know or care about those so its up to the approval holder to supply the amendment at the time of purchase. Need to know what serial number you have when ordering from the mothership. They can also be changed via airworthiness directives.

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And I'm sure the most recent weight and balance for the aircraft would have the info I'm looking for. Sadly, I'm not near the airport right now and can't look at them. My plan is to snap photos of the weight and balance for all aircraft in their fleet the next time I go just so I have the data for each plane and can ensure I am within limits when I fly with my family. With a 2300 lb max gross weight, I can take all family members, but can't take full fuel. At 2450, I can take all members and full fuel. I promise you, my wife will feel more comfortable knowing we have full fuel tanks vs tanks with less fuel, even if it is a moot point since I would never plan to fly with less than an hour of reserve when I land at my final destination.
 
Will Kumley said:
And I'm sure the most recent weight and balance for the aircraft would have the info I'm looking for. Sadly, I'm not near the airport right now and can't look at them. My plan is to snap photos of the weight and balance for all aircraft in their fleet the next time I go just so I have the data for each plane and can ensure I am within limits when I fly with my family. With a 2300 lb max gross weight, I can take all family members, but can't take full fuel. At 2450, I can take all members and full fuel. I promise you, my wife will feel more comfortable knowing we have full fuel tanks vs tanks with less fuel, even if it is a moot point since I would never plan to fly with less than an hour of reserve when I land at my final destination.
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yeah my dad like carrying an insane amount of gas everywhere too. The 177 I have holds 48 gallons and won’t burn 8 gallons an hour at favorite cruise settings... so yeah, he would take an extra 5 hours of fuel to fly around the patch all the time.
 
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Will Kumley said:
The real reason this whole thread got started though was more from the change in max gross weight on the checklist. ... I just couldn't realistically see how the aircraft max gross weight would increase by 150 pounds. In theory I could see an engine upgrade allowing it, but I'm sure there is more to it than just an engine upgrade when it comes to determining max gross weight. ...
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For a Piper Warrior II (PA-28-161) one can buy a paper-only STC (SA00397NY) which raises the MGW 115 pounds from 2325 to 2440.
 
On a Boeing 727 you can buy an STC that makes it "noise" compliant.........and doesn't do ANYTHING to the airplane................ or the time I realized Jim Raisbeck was a genius.
 
Domenick said:
For a Piper Warrior II (PA-28-161) one can buy a paper-only STC (SA00397NY) which raises the MGW 115 pounds from 2325 to 2440.
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kgruber said:
On a Boeing 727 you can buy an STC that makes it "noise" compliant.........and doesn't do ANYTHING to the airplane................ or the time I realized Jim Raisbeck was a genius.
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Why am I not surprised. I guess I was thinking there would be a bit more involved in something like this but I guess it is true. With enough money, one could do anything they wanted.
 
Update, got a copy of the W&B for the aircraft in question. Looks like they just copied a checklist they had for their 172R which has a higher max gross weight.
 
As regards the Piper Warrior II MGW STC: The original PA-28-151 (Warrior I) Type Certificate listed normal MGW as 2325 lbs. When Piper filed the Type Certificate for the PA-28-161 (Warrior II) with 10 HP more than the -151 they simply used most of the original -151 TC. The paper-only STC simply takes into account the power difference between the -151 and -161.

No I have not bought it.

I can't explain the B-727 noise compliance STC.
 
midlifeflyer said:
I pointed out a number of errors in both. He wrote back, "Read the POH!!" I replied, "Read the right parts of the POH."
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This made me LOL.

For the OP, everybody here has you on the right track, and good eye noticing discrepancies — many people will simply miss things like the POH not matching the aircraft at all.

As another example of this, my airplane has a significant STC on it to add the STOL kit and capabilities. That STC also mandates POH changes. It also forces a need to maintain an ASI that reads in MPH, so we have a dual MPH/Knots ASI in the panel.

Have fun researching that specific aircraft!
 
I bought my 1980 Pa28-181 new and would get updates over the years until about 1996. Recently got another a year ago. I called Piper to find out if I had missed a few others. Fortunately, there were not many except for some in the early late 1990’s and early 2000s which I’m trying to track down without them charging me for them.

By the way, my POH indicates my redline is 2700rpm for 5 minutes, but then 2650 afterward. The online POH which shows a picture of an early 2000’s PA28-181 indicates the redline of 2700rpm without anything about the need to reduce to 2650. Anyone know why, and whether I can ignore the 2650 limitation for my aircraft?
 
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