APR CR-6 VS Jeppesen CR-3
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APR CR-6 VS Jeppesen CR-3
Hi all,
New user, first post, but a semi-frequent reader.
About to start my EASA ATPL(H) in a few weeks and in need of a flight computer. I'm leaning toward a CR computer in the 6" size. There are two brands I know of offering this, APR and Jeppesen as mentioned in the title.
Now I wonder, are there anyone here having hands-on experience of BOTH and are willing to share their view of pros and cons of both, not just "read the specifications"-knowledge which I already have myself?
I know they are more or less identical when it comes to features (APR has a few extra, or?) with basically the same price, but how about:
Readability?
Usability?
Durability?
Accuracy? (the "APR Microset"?)
Built-quality?
And also quality of the provided manual? (the Jeppesen is often referred to as "crap", I've heard)
Any thing else that might differ?
BR
/H
New user, first post, but a semi-frequent reader.
About to start my EASA ATPL(H) in a few weeks and in need of a flight computer. I'm leaning toward a CR computer in the 6" size. There are two brands I know of offering this, APR and Jeppesen as mentioned in the title.
Now I wonder, are there anyone here having hands-on experience of BOTH and are willing to share their view of pros and cons of both, not just "read the specifications"-knowledge which I already have myself?
I know they are more or less identical when it comes to features (APR has a few extra, or?) with basically the same price, but how about:
Readability?
Usability?
Durability?
Accuracy? (the "APR Microset"?)
Built-quality?
And also quality of the provided manual? (the Jeppesen is often referred to as "crap", I've heard)
Any thing else that might differ?
BR
/H
If you search the forums, you'll find quite a few discussions about whiz wheels. Generally, you'll find that UK origin instructors only support slide-type computers. Others, such as myself, are firmly in favour of CR types like Jeppesen's or APR Industry's models.
I've used both. I think the CR type is the winner - and is cheaper. I used a Kane slide for my Oz commercial, and the 3 3/4" CR
(smallest, and therefore least accurate) model for my Oz instrument, Oz ATPL, FAA ATPL, & UK ATPL exams. There were around 6-10 Oz/Kiwi expats on my UK ATPL exam course. All bar one used a CR. Our CR derived answers had a tighter cluster of answers around the correct answer than did the CRP/slide users in our class.
The catch is that few, if any, UK (and other EASA?) instructors have a clue about using the CR type so you won't get much support from them (other than basic calculations). The instruction book is fine, however. I taught myself to use a CR from it for my Oz IR exams in 1987 and have used one since - including in the real world of piloting for a living.
Notes:
* CR types are available in 3 sizes: 3.75", 4.25 (or it might be 4.5"), and ~6.0". Like all analogue flight computers/slide rules size improves accuracy. You don't need the 6" for the exams however. If you're precise/careful then either of the others are fine. HINT: On all of them you will need to interpolate for effective TAS/HDG less than 10 deg (you'll know what I mean if you start using one), even though the book says it can be ignored. That's exams for you...
* Jeppesen now only sell the 4.x size & the 6" size. APR industries still sell all three. I've used both Jepp & APR's types. No difference that I've noticed.
I've used both. I think the CR type is the winner - and is cheaper. I used a Kane slide for my Oz commercial, and the 3 3/4" CR
(smallest, and therefore least accurate) model for my Oz instrument, Oz ATPL, FAA ATPL, & UK ATPL exams. There were around 6-10 Oz/Kiwi expats on my UK ATPL exam course. All bar one used a CR. Our CR derived answers had a tighter cluster of answers around the correct answer than did the CRP/slide users in our class.
The catch is that few, if any, UK (and other EASA?) instructors have a clue about using the CR type so you won't get much support from them (other than basic calculations). The instruction book is fine, however. I taught myself to use a CR from it for my Oz IR exams in 1987 and have used one since - including in the real world of piloting for a living.
Notes:
* CR types are available in 3 sizes: 3.75", 4.25 (or it might be 4.5"), and ~6.0". Like all analogue flight computers/slide rules size improves accuracy. You don't need the 6" for the exams however. If you're precise/careful then either of the others are fine. HINT: On all of them you will need to interpolate for effective TAS/HDG less than 10 deg (you'll know what I mean if you start using one), even though the book says it can be ignored. That's exams for you...
* Jeppesen now only sell the 4.x size & the 6" size. APR industries still sell all three. I've used both Jepp & APR's types. No difference that I've noticed.
Last edited by Tinstaafl; 6th Aug 2015 at 02:11.
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The CR-3 is not expensive and does the job really well. The very small one needed glasses to read it! Not used the other specifically, but they look to be exactly the same.
If you intend to take your exams in UK, the CR-3 is the only one of the two mentioned that is allowed in the exams.
There used to be a large workbook for the Jep, but it's hard to get these days. Since you can't take PMs, here is a link to a new version - Pilot Training & Ground Studies - Electrocution's Aviation Books.
Phil
If you intend to take your exams in UK, the CR-3 is the only one of the two mentioned that is allowed in the exams.
There used to be a large workbook for the Jep, but it's hard to get these days. Since you can't take PMs, here is a link to a new version - Pilot Training & Ground Studies - Electrocution's Aviation Books.
Phil
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That's not a good idea! 
The questions are no longer based on it. If you want a slide computer and want to pay £70, the AFE ARC 2 is of much better construction, as is the Transair effort. Back in the day, the CAA used to keep 3 CRP-5s in their office to take an average, as it was so badly made, aside from inheriting some inaccuracies from the RAF one on which it was based that we had to use (with arrows all over it - you felt like a prisoner!) I don't think the situation is much different today.
The sine based machines like the CR-3 are much easier to use.
G
The questions are no longer based on it. If you want a slide computer and want to pay £70, the AFE ARC 2 is of much better construction, as is the Transair effort. Back in the day, the CAA used to keep 3 CRP-5s in their office to take an average, as it was so badly made, aside from inheriting some inaccuracies from the RAF one on which it was based that we had to use (with arrows all over it - you felt like a prisoner!) I don't think the situation is much different today.The sine based machines like the CR-3 are much easier to use.
G
I bought a Cx2 18 years ago for PPL and it is still working on the same set of batteries. I tried the manual E6B during CFI training and am glad I didn't have to use it. Gotta keep with the times...
That said an HP-12C calculator from the 70s will still blow anything else out of the water. Get the simplest computer that is allowed, know it inside and out, and you'll be fine.
That said an HP-12C calculator from the 70s will still blow anything else out of the water. Get the simplest computer that is allowed, know it inside and out, and you'll be fine.
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Did you know on the HPs that you can do C of G with minimal effort using the statistics function? Real quick. Will post the instructions if anyone's interested.
OK, by popular demand
I use a 15C myself (showoff) but the same instructions work on an 11C or any HP with the statistical function marked with the sigma (don't know how to get that here). The only difference lies in the memory stores that need to be recalled. On the 15C it is 7 and 5 - on the 11C IFIRC it will be 5 and 3 (look on the back of the computer).
R7 totals the x and y values (weight x moment arm), while R5 simply adds up x (aircraft weight).
So, taking an aircraft BEM of 3000 lbs and 117.5, you would key in 3000 <Enter> then 117.5 followed by the sigma button.
Once you have finished doing evertthing else, press RCL7, then RCL5, then the divide button. Simples!
Phil
OK, by popular demand
I use a 15C myself (showoff
) but the same instructions work on an 11C or any HP with the statistical function marked with the sigma (don't know how to get that here). The only difference lies in the memory stores that need to be recalled. On the 15C it is 7 and 5 - on the 11C IFIRC it will be 5 and 3 (look on the back of the computer).R7 totals the x and y values (weight x moment arm), while R5 simply adds up x (aircraft weight).
So, taking an aircraft BEM of 3000 lbs and 117.5, you would key in 3000 <Enter> then 117.5 followed by the sigma button.
Once you have finished doing evertthing else, press RCL7, then RCL5, then the divide button. Simples!
Phil
Last edited by paco; 2nd Aug 2015 at 12:41.
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@Tinstaafl
Thank you for your elaborating answer. I have already read many threads regarding FCs and come to the conclusion I like the CR ones. But your answer fortified that opinion though.
What I asked for was a comparison between the two, and according to you, at the end, there's no difference. Good.
@Phil
Thank you for the heads up about what computer is allowed. I will take my tests in Sweden, but will most likely buy the CR-3 just in case, I also check with our authority if it's valid here.
And thanks for the link, will check it out. I also have seen that you released a navigation book based on the CR-3. As a happy owner of your pro helicopter pilot book I guess that one is good to.
Ps I'm the "Atmosphere Guy" mailing with you earlier this summer...
Edit: ha, I saw now that the link you gave was for that navigation one
@all others
Thanks for your thoughts regarding this, appreciated, although the lack of APR "reviews"
Thank you for your elaborating answer. I have already read many threads regarding FCs and come to the conclusion I like the CR ones. But your answer fortified that opinion though.
What I asked for was a comparison between the two, and according to you, at the end, there's no difference. Good.
@Phil
Thank you for the heads up about what computer is allowed. I will take my tests in Sweden, but will most likely buy the CR-3 just in case, I also check with our authority if it's valid here.
And thanks for the link, will check it out. I also have seen that you released a navigation book based on the CR-3. As a happy owner of your pro helicopter pilot book I guess that one is good to.
Ps I'm the "Atmosphere Guy" mailing with you earlier this summer...
Edit: ha, I saw now that the link you gave was for that navigation one
@all others
Thanks for your thoughts regarding this, appreciated, although the lack of APR "reviews"
Last edited by Holton181; 3rd Aug 2015 at 07:34.
I've had 3 x 3.75" CRs since 1987. 1st was a 2nd hand APR (grey colour). Used it for Oz instrument & ATPLs, & US ATP. At some point in the mid to late 90's I left it in the car one summer afternoon & it softened & bent along one edge when something rested against. I finally got sick of the bend and replaced it with the same sized Jepp (also grey). Pretty sure that was the one I used for my UK ATPL in '99.
A couple of years ago I replaced it with a 3.75" APR (now only sold in yellow. I think it gives better contrast so minor yay, I suppose) when my Jepp had become rather scratched & worn. Can't say I've noticed any significant difference. The hub is slightly different and I'd rather my new APR had a bit more friction to resist rotation, but other than that? Nothing I can think off.
A friend recently borrowed my APR CR for his FAA IR theory, and my old Jepp was put back to work.
All my CRs have been the smallest 3.75" size. I like the smaller size's easier fit into clothes & backpack/bag pockets. I've never had trouble getting accurate answers from them in all those exams I've done.
A couple of years ago I replaced it with a 3.75" APR (now only sold in yellow. I think it gives better contrast so minor yay, I suppose) when my Jepp had become rather scratched & worn. Can't say I've noticed any significant difference. The hub is slightly different and I'd rather my new APR had a bit more friction to resist rotation, but other than that? Nothing I can think off.
A friend recently borrowed my APR CR for his FAA IR theory, and my old Jepp was put back to work.
All my CRs have been the smallest 3.75" size. I like the smaller size's easier fit into clothes & backpack/bag pockets. I've never had trouble getting accurate answers from them in all those exams I've done.
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@Tinstaafl
Again, thank you.
I had more or less desided for a Jeppesen CR-3 when I read your comparison.
Even not that big differences, the somewhat higher contrast and slightly higher rotation resistance on the APR may make me reconsider.
I have also asked the responsible authority and in Sweden and there are no restrictions on what non-electronic flight computer I can chose from.
Other than that, a new candidate has come to my attention, the ASA E6B Circular Flight Computer. I guess its the same as the others? any one with experience of that?
(I guess I'll be happy with whatever computer I chose)
Again, thank you.
I had more or less desided for a Jeppesen CR-3 when I read your comparison.
Even not that big differences, the somewhat higher contrast and slightly higher rotation resistance on the APR may make me reconsider.
I have also asked the responsible authority and in Sweden and there are no restrictions on what non-electronic flight computer I can chose from.
Other than that, a new candidate has come to my attention, the ASA E6B Circular Flight Computer. I guess its the same as the others? any one with experience of that?
(I guess I'll be happy with whatever computer I chose)
E6Bs are slide type computers ie the navigation solution requires plotting vectors on a scale that slides through the circular slide rule. Be careful with what E6B you buy. Not all of them are suitable for high speed flight, lacking appropriate scales & windows for Mach problems. All CR types on the market are fine for high speed/Mach solutions.
It was my Jepp that had the better (higher) friction.
It was my Jepp that had the better (higher) friction.
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The ASA E6B Circular Flight Computer is actually a CR version of the regular one, but without the ruler and with the CR wind calculator at the "backside". I think it's fairly new. But I keep away from it.
Now...
I like contrast... and I like friction...
ARRRGGGH! So hard to choose!!!
I'll think it will be the one I feel for at the moment of ordering...or rolling a dice.
Thank you both for your input, much appreciated. I hoped to learn which one was the best to buy, but lerned they were equally good. Slightly harder to choose, but I will be equally happy with any of them.
BR
/H
Now...
I like contrast... and I like friction...
ARRRGGGH! So hard to choose!!!
I'll think it will be the one I feel for at the moment of ordering...or rolling a dice.
Thank you both for your input, much appreciated. I hoped to learn which one was the best to buy, but lerned they were equally good. Slightly harder to choose, but I will be equally happy with any of them.
BR
/H
ASA making a CR type is new to me. I wonder when they started? No matter. It should work for you as well as the others. Bear in mind you really don't need a 6" CR to pass the exams.
Many I know used one in the 4.xx" size. I used a 3.75" one for all of my exams after CPL.
Many I know used one in the 4.xx" size. I used a 3.75" one for all of my exams after CPL.
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So...
A small uppdate on this.
It ended up in me buying the APR CR-6. I like yellow, and it was (suposed to be) cheaper. I ordered it for €31 with a shipping kost of €8, in total €39, direkt payment and 2 weeks delivery. The day after I put my order I had my first visit to the local airport pilot shop. They had the Jeppesen for €34...
Never the less I'm happy with it so far, but I'm alone to learn it, my ground school instructors did not even know about the existence of the CR computers.
For the record, the Jeppesen has one extra features compared to the APR. On the Jeppesen you can do some pressure patern calculations.
I don't miss that on the APR...
@Tinstaafl
I appreciate you recommending the smaller ones, but since I'm not going to use it during flight (helicopter) I thought it was as well to by the big one.
BR
/H
A small uppdate on this.
It ended up in me buying the APR CR-6. I like yellow, and it was (suposed to be) cheaper. I ordered it for €31 with a shipping kost of €8, in total €39, direkt payment and 2 weeks delivery. The day after I put my order I had my first visit to the local airport pilot shop. They had the Jeppesen for €34...
Never the less I'm happy with it so far, but I'm alone to learn it, my ground school instructors did not even know about the existence of the CR computers.
For the record, the Jeppesen has one extra features compared to the APR. On the Jeppesen you can do some pressure patern calculations.
I don't miss that on the APR...
@Tinstaafl
I appreciate you recommending the smaller ones, but since I'm not going to use it during flight (helicopter) I thought it was as well to by the big one.
BR
/H
