PA-28 Archer Technical Information?
Thread Starter
Joined: Dec 2017
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From: London
PA-28 Archer Technical Information?
Hi,
Let me start by firstly apologizing if this has been posted in the wrong section, there are quite a few! I am an Aerospace Engineering (BEng) Student from the UK that is currently investigating flow separation control techniques and their application to GA aircraft. The study looks specifically on the wheel fairings (or Wheel pants) on the PA-28 Archer.
I need to reproduce these in 3D to allow me to CFD test them. However, dimensions seem to be an elusive holy grail! If anyone is able to help either with High Resolution Images or in any other way, it would be greatly appreciated!
Let me start by firstly apologizing if this has been posted in the wrong section, there are quite a few! I am an Aerospace Engineering (BEng) Student from the UK that is currently investigating flow separation control techniques and their application to GA aircraft. The study looks specifically on the wheel fairings (or Wheel pants) on the PA-28 Archer.
I need to reproduce these in 3D to allow me to CFD test them. However, dimensions seem to be an elusive holy grail! If anyone is able to help either with High Resolution Images or in any other way, it would be greatly appreciated!
Joined: Jun 2005
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From: USA
I did a quick search on that very popular search engine using the search term "PA28-181 wheel pants" and found a multitude of images, after-market products and claims of up to 10 knots greater speed! In my experience though, these additional speed claims tend to be a little bit "optimistic" shall we say? We run a whole fleet of Archers with no wheel pants installed. Most of them will top out at 120-125 KTAS. If they had factory wheel pants, I believe we might get as much as 128!
Joined: Jan 1999
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From: north of barlu
Performance loss
There is a performance write down for removeing the wheel fairings, if my memory is correct it is about 3%.
This would put the numbers quoted by westhawk roughly in the ballpark.
This would put the numbers quoted by westhawk roughly in the ballpark.
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From: UK
If it's the -181 archer you are looking at, the external shap e is identical to the -161 Warrior II. Those are readily found at most GA airfields, and the odds are that if you phone in advance and ask, nobody will mind you going and measuring one up.
One warning however - most clubs operating off grass probably removed them long ago as a nuisance. So either you want to see if they have some buried in a cupboard in the back of a hangar, or a flying club with all hard runways and maneuvering surfaces.
G
One warning however - most clubs operating off grass probably removed them long ago as a nuisance. So either you want to see if they have some buried in a cupboard in the back of a hangar, or a flying club with all hard runways and maneuvering surfaces.
G
Thread Starter
Joined: Dec 2017
Posts: 5
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From: London
I did a quick search on that very popular search engine using the search term "PA28-181 wheel pants" and found a multitude of images, after-market products and claims of up to 10 knots greater speed! In my experience though, these additional speed claims tend to be a little bit "optimistic" shall we say? We run a whole fleet of Archers with no wheel pants installed. Most of them will top out at 120-125 KTAS. If they had factory wheel pants, I believe we might get as much as 128!
- George
Thread Starter
Joined: Dec 2017
Posts: 5
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From: London
If it's the -181 archer you are looking at, the external shap e is identical to the -161 Warrior II. Those are readily found at most GA airfields, and the odds are that if you phone in advance and ask, nobody will mind you going and measuring one up.
One warning however - most clubs operating off grass probably removed them long ago as a nuisance. So either you want to see if they have some buried in a cupboard in the back of a hangar, or a flying club with all hard runways and maneuvering surfaces.
G
One warning however - most clubs operating off grass probably removed them long ago as a nuisance. So either you want to see if they have some buried in a cupboard in the back of a hangar, or a flying club with all hard runways and maneuvering surfaces.
G
-George
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Joined: Jun 1999
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From: MAN. UK.
Hello George.
As someone who owns a 77 Archer the subject of wheel spats is one close to my heart as the pre 78 models had smaller spats and not the 'pants' common to most peoples impression of the aircraft. The difference is that the earlier ones are worth 3-4 knots and the full leg pants around 7-8.
If you would like me to forward the relevant performance graph from my POH I would be happy to do so. PM me an email address and I'll mail it over.
As someone who owns a 77 Archer the subject of wheel spats is one close to my heart as the pre 78 models had smaller spats and not the 'pants' common to most peoples impression of the aircraft. The difference is that the earlier ones are worth 3-4 knots and the full leg pants around 7-8.
If you would like me to forward the relevant performance graph from my POH I would be happy to do so. PM me an email address and I'll mail it over.
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From: UK
I used to have a PA28-161 that had spats, which I think were the smaller ones. I'd agree with the 3-4 knot decrement in cruise at about 70% power.
Vaguely close to LCY I'd try North Weald (North Weald Flying Group are nice folks and have a suitable aeroplane), Fairoaks and Booker.
If you get sufficiently desperate, drop me a line. I don't presently have access to a -161, but do have access to a -151 with spats at an airfield in the Midlands. I don't know how similar the fuselage and undercarriage are between that and the Archer however, I do know that the wings are different.
G
Vaguely close to LCY I'd try North Weald (North Weald Flying Group are nice folks and have a suitable aeroplane), Fairoaks and Booker.
If you get sufficiently desperate, drop me a line. I don't presently have access to a -161, but do have access to a -151 with spats at an airfield in the Midlands. I don't know how similar the fuselage and undercarriage are between that and the Archer however, I do know that the wings are different.
G
Joined: Jun 2002
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From: UK
The -151, -161 and -181 have the same airframe.
Archer (181) is different firewall forward (engine, cowlings, spinner, prop). Back seats are different.
Early -151 had a different aileron set up with dropped hinges and linked to the rudder. Later -151 were identical to the -161 except the engine.
As others have said, earlier spats/leg fairings were much smaller and didn’t fully enclose the wheel or undercarriage leg.
Archer (181) is different firewall forward (engine, cowlings, spinner, prop). Back seats are different.
Early -151 had a different aileron set up with dropped hinges and linked to the rudder. Later -151 were identical to the -161 except the engine.
As others have said, earlier spats/leg fairings were much smaller and didn’t fully enclose the wheel or undercarriage leg.
Last edited by smarthawke; 25th December 2017 at 09:30.
Joined: Dec 2001
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From: GA, USA
Alternatively you may want to get in touch with the companies that actually design and make ( aftermarket) “speed” parts like
http://www.knots2u.net
http://www.loprestiaviation.com/speed-spats-1.html?___store=russian&___from_store=english
I’m sure they’ll be happy to help an engineering student.
http://www.knots2u.net
http://www.loprestiaviation.com/speed-spats-1.html?___store=russian&___from_store=english
I’m sure they’ll be happy to help an engineering student.
Joined: Aug 2007
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From: 18nm NE grice 28ft up
I needed to replace the spats on the '78 181 Archer I owned. I got replacements which had been on a similar age 161 Warrior.
The mains were fine but the nose wheel spat did not fit as the Archer had a bigger tyre. The spat looked the same but there must have been subtle differences.
The mains were fine but the nose wheel spat did not fit as the Archer had a bigger tyre. The spat looked the same but there must have been subtle differences.
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From: UK
Just a passing thought about nosewheel spats - they can have a marked tendency to reduce directional static stability and to increase rudder power. I'm not aware of this being a problem with the PA28, but it certainly has been on some other similarly configured types.
G
G
Thread Starter
Joined: Dec 2017
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From: London
My apologies for the delay in replying, Christmas and all...!
Thanks that would be fantastic! However, I cannot seem to find any way of sending a PM (Maybe due to probationary status?)
That would be beyond helpful! It would be a case of organising a time and date. I would need to return to my university first to see if they have any newfangled metrology equipment that I can borrow to make life easy.
Thanks! I will be sure to drop them a line. However, you would be surprised how reluctant some companies are at sharing information even for academia!
Hello George.
As someone who owns a 77 Archer the subject of wheel spats is one close to my heart as the pre 78 models had smaller spats and not the 'pants' common to most peoples impression of the aircraft. The difference is that the earlier ones are worth 3-4 knots and the full leg pants around 7-8.
If you would like me to forward the relevant performance graph from my POH I would be happy to do so. PM me an email address and I'll mail it over.
As someone who owns a 77 Archer the subject of wheel spats is one close to my heart as the pre 78 models had smaller spats and not the 'pants' common to most peoples impression of the aircraft. The difference is that the earlier ones are worth 3-4 knots and the full leg pants around 7-8.
If you would like me to forward the relevant performance graph from my POH I would be happy to do so. PM me an email address and I'll mail it over.
Thanks! I will be sure to drop them a line. However, you would be surprised how reluctant some companies are at sharing information even for academia!
Moderator
Joined: Feb 2000
Aviation Qualifications: CPL
Posts: 14,479
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From: UK
A hint that may be useful. Investigate first
- the complexity with which your CFD modelling software can genuinely take the shape you want to model.
- what you can do with ESDU data sheets.
This should tell you how accurately you genuinely need to measure up the spats.
G
- the complexity with which your CFD modelling software can genuinely take the shape you want to model.
- what you can do with ESDU data sheets.
This should tell you how accurately you genuinely need to measure up the spats.
G
